• Holtedahl, Robin; Hott, Alexandra Christine; Hansen, Inger Johanne Widding; Bjørneboe, John Andreas & Brox, Jens Ivar (2026). Magnitude of the placebo response across non-surgical treatment modalities used for knee osteoarthritis: A meta-analysis with meta-regression. Osteoarthritis and Cartilage Open. 8(3). doi: 10.1016/j.ocarto.2026.100861. Full text in Research Archive
• Nuri, Sebastian Gautland; Dahlen, Sara Christina; Bjørneboe, John Andreas & Andersen, Thor Einar (2026). Characteristics of match-related head injuries in professional women's football: A prospective cohort study. Journal of Science and Medicine in Sport. ISSN 1440-2440. doi: 10.1016/j.jsams.2026.04.010. Full text in Research Archive
• Bjorland, Siri; Bjørneboe, John Andreas; Røe, Cecilie; Taso, Mirad; Engebretsen, Kaia Beck & Skatteboe, Sigrid [Show all 9 contributors for this article] (2026). Cognitive functional therapy for persistent neck pain. Pain Management. p. 1–9. doi: 10.1080/17581869.2026.2625646. Full text in Research Archive Show summary

  Aims: Persistent neck pain is a leading cause of years lived with disability. The aim of the current study is to describe and evaluate cognitive functional therapy for patients with persistent neck pain. Methods: We recruited 74 patients (73% women) aged 22–76 years, with persistent neck pain. The outcomes were neck pain at activity and rest measured by 11-point numeric rating scales (NRS), disability by Neck Disability Index (NDI) (0–100), Fear Avoidance Beliefs Questionnaire (FABQ), Hopkin Symptom Check List (HSCL-10) at baseline and post-treatment. The treatment program included 5 sessions and focused on cognitive strategies and exposure to physical activities. Results: Sixty (81%) patients had follow-ups. Neck pain during activity was reduced by a mean of 3.3 (95% Confidence interval (CI) 2.6 to 3.2) and 2.5 (95% CI 1.9 to 3.1) at rest. NDI was reduced by 16.3 (95% CI 12.0–20.5). Similar large improvements were observed for FABQ and HSCL-10. Ninety-eight percent of the participants reported that they would recommend the program to other patients. Conclusions: Clinically relevant improvements were observed in pain, disability, fear-avoidance beliefs, and emotional distress following CFT in patients with persistent neck pain.

• Bjørneboe, John Andreas; Brox, Jostein Skranes; Myhre, Kjersti; Taso, Mirad; Werner, Erik Lønnmark & Røe, Cecilie [Show all 7 contributors for this article] (2025). Henvisninger til spesialisthelsetjenesten for pasienter med smerter i nakke og rygg. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 145(9). doi: 10.4045/tidsskr.24.0324. Full text in Research Archive
• Dahlen, Sara Christina; Bjørneboe, John Andreas; Sandmo, Stian Kirkerud; Bache-Mathiesen, Lena Kristin & Andersen, Thor Einar (2025). Video analysis of head impacts in top-level female football players: a cohort study. Science and medicine in football. ISSN 2473-3938. doi: 10.1080/24733938.2025.2548209. Full text in Research Archive Show summary

  This study aimed at exploring the exposure of head impacts, i.e. headers and non-headers, in top-level female football players. The study included all teams (n = 10) and players (n = 238) in the Norwegian Women’s Premier League during the 2023 season. Video analysis was used to register headers and non-headers in the 135 matches of the season. Potential head injuries were compared between video signs and medical reports. The header and non-header incidences were estimated per 90 match minutes with 95% confidence intervals (CI). We observed 9364 headers and 233 non-headers in 135 matches. Nine non-headers resulted in a head injury (all concussions), players’ time loss ranging from 5 to 87 days. The highest number of headers performed by a single player in a match was 22. The total number of headers performed during a match varied between 34 and 125. Defenders had an estimated 4.2 (CI = 3.9–4.3), midfielders 2.9 (CI = 2.7–3.0), and forwards 2.6 (CI = 2.5–3.1) headers per match. There was a positive correlation between heading frequency and age. Forwards were the players most exposed to non-headers, with an estimated 0.09 per match. Most non-headers were caused by unintentional head-to-ball contact. We found that defenders had the highest header frequency. Header frequencies varied substantially between players and from match to match. Forwards had the highest risk of non-headers. Nine non-headers resulted in head injuries.

• Bjørneboe, John Andreas; Røe, Cecilie; Brox, Jens Ivar; Sveinall, Håkon; Ignatius, Janica Sofia & Wilhelmsen, Maja [Show all 7 contributors for this article] (2025). Responsiveness and minimal important change of neck disability index and numeric pain rating scale for neck patients in the Norwegian neck and back register. European spine journal. ISSN 0940-6719. 34(6), p. 2219–2226. doi: 10.1007/s00586-025-08836-7. Full text in Research Archive Show summary

  Purpose To evaluate the responsiveness and the minimal important change (MIC) of Neck Disability Index (NDI) and pain during activity by the numeric rating scale (NRSa) in the Norwegian neck and back registry (NNRR). Materials and methods Participants with neck pain responding to baseline, 6 and 12-months follow-up in the NNRR were included. Responsiveness was calculated using the area under the receiver operating characteristic (ROC). The minimal important change (MIC) was calculated with an anchor-based method and distribution-based methods. For the anchor-based method we used the Patient Global Impression of Change (PGIC) as the anchor. The PGIC was on a 7-point Likert scale, and trichotomized into three ordinal categories. Results A total of 551 patients with neck pain were included. Among these patients, 60% were women with an average age of 48, and 63% had experienced neck pain for more than one year. For improved patients NDI and NRSa had adequate responsiveness at both follow-ups. MIC calculations using an anchor-based method were more accurate than those using a distribution-based method, which fell below the measurement error for the instruments. Using anchor-based calculation of MIC, the MIC for NDI was 17 at the 6-months follow-up and 9 at 12-months follow-up. Correspondingly, NRSa had a MIC of 2.5 at both follow-ups. Conclusion NDI and NRSa were responsive at both 6-months and 12-months follow-up and can be used in registries following patients with neck pain over time.

• Melås, Thea Morin; Bjørneboe, John Andreas; Juel, Niels Gunnar; Wefring, Maren Lunder; Skatteboe, Sigrid & Killingmo, Rikke Munk [Show all 13 contributors for this article] (2025). Self-management versus usual care for greater trochanteric pain syndrome (the HIPS trial): Study protocol for a randomised controlled trial. BMJ Open. 15(4). doi: 10.1136/bmjopen-2024-090688. Full text in Research Archive
• Skatteboe, Sigrid; Røe, Cecilie; Heide, Marte; Brox, Jens Ivar; Ignatius, Janica Sofia & Bratsberg, Andrea Mathisen [Show all 8 contributors for this article] (2024). Responsiveness and minimal important change of specific and generic patient-reported outcome measures for back patients: the Norwegian Neck and Back Register. European spine journal. ISSN 0940-6719. 33(8), p. 2960–2968. doi: 10.1007/s00586-024-08394-4. Full text in Research Archive Show summary

  Purpose To evaluate responsiveness and minimal important change (MIC) of Oswestry Disability Index (ODI), pain during activity on a numeric rating scale (NRSa) and health related quality of life (EQ-5D) based on data from the Norwegian neck and back registry (NNRR). Methods A total of 1617 patients who responded to NNRR follow-up after both 6 and 12 months were included in this study. Responsiveness was calculated using standardized response mean and area under the receiver operating characteristic (ROC) curve. We calculated MIC with both an anchor-based and distribution-based method. Results The condition specific ODI had best responsiveness, the more generic NRSa and EQ-5D had lower responsiveness. We found that the MIC for ODI varied from 3.0 to 9.5, from 0.4 to 2.5 for NRSa while the EQ5D varied from 0.05 to 0.12 depending on the method for calculation. Conclusion In a register based back pain population, the condition specific ODI was more responsive to change than the more generic tools NRSa and EQ5D. The variations in responsiveness and MIC estimates also indicate that they should be regarded as indicative, rather than fixed estimates.

• Ignatius, Janica Sofia; Røe, Cecilie; Perrin, Paul B.; Skatteboe, Sigrid; Brox, Jens Ivar & Kielland, Maja Garnaas [Show all 7 contributors for this article] (2024). Influence of nationality on the trajectories of pain, disability and health related quality of life in neck and back patients – The Norwegian Neck and Back Registry. Musculoskeletal Science and Practice. ISSN 2468-8630. 74. doi: 10.1016/j.msksp.2024.103193. Full text in Research Archive Show summary

  Purpose The aim of the current study was to examine differences in trajectories of pain, disability, and health related quality of life (HRQOL) between non-Norwegian and Norwegian patients with neck and back pain over 12 months. Methods The study is based on data from the Norwegian Neck and Back Registry (NNRR). The data include demographics and patient-reported outcome measures such as pain rating, the Oswestry Disability Index and HRQOL. Data were collected at baseline, 6 and 12 months after consultation for neck and back pain in specialist health care. Results A total of 5012 patients were included. We found a significant main effect of nationality. Non-Norwegian patients showed higher levels of pain and disability and lower HRQOL than Norwegian patients. Both patient groups exhibited an improvement in all three outcomes at 6- and 12-month follow-ups. The improvement was similar for pain with the greatest improvement taking place during the first 6 months and then slightly flattening out. For disability and HRQOL, we observed a differential effect over time as a function of nationality. Both groups reported an improvement the first 6 months, however, while the Norwegian patients continued their improvement to 12 months, non-Norwegian patients had increasing disability and lower HRQOL at 12 months. Conclusion Both patient groups improved over the 12-month period. Non-Norwegian patients showed an overall higher level of pain, disability and lower HRQOL compared to Norwegian patients, with a differential effect over time as a function of nationality for disability and HRQOL. Suggesting that future studies should focus on potential systemic barriers that may affect the recovery of neck and back patients based on nationality.

• Bjørneboe, John Andreas; Bratsberg, Andrea Mathisen; Brox, Jens Ivar; Skatteboe, Sigrid; Wilhelmsen, Maja & Samuelsen, Kjetil Magne [Show all 10 contributors for this article] (2024). Symptom burden and follow-up of patients with neck and back complaints in specialized outpatient care: a national register study. Scientific Reports. 14(1). doi: 10.1038/s41598-024-53879-3. Full text in Research Archive Show summary

  Back and neck pain are common in the population, especially among immigrants. In Norway’s specialist care system, treating these patients typically involves a multidisciplinary approach based on the biopsychosocial model. However, language and cultural differences may create barriers to participation. Immigrants are often underrepresented in clinical studies, but a register‑based approach can enhance their participation in research. This study aimed to compare both the symptom burden, and treatment, among Norwegians, non‑Norwegians, and patients requiring translator service for back and neck pain within the Norwegian specialist care system. The Norwegian neck and back registry is a National Quality Register, established in 2012 and fully digitized in late 2020. The baseline data includes demographics and patient recorded outcome measures including Oswestry Disability Index, Fear‑Avoidance Beliefs, pain rating on a numeric rating scale, Hopkins Symptom Checklist and EuroQol five‑dimensional questionnaire on health related quality of life. During the two‑year study period, a total of 14,124 patients were invited, and 10,060 (71%) participated. Norwegian patients reported less pain, better function assessed by Oswestry Disability Index, lower fear avoidance beliefs, less emotional distress, and higher health related quality of life compared to non‑Norwegians. We found that patients with female gender, who were younger, more educated and exhibited fear‑ avoidance behavior were significantly more likely to receive multidisciplinary treatment. We found no difference in the proportion of Norwegian and non‑Norwegian patients receiving multidisciplinary treatment [odds ratio (OR) 1.02 (95% confidence interval (CI) 0.90–1.16)]. However, patients needing a translator were less likely to receive multidisciplinary treatment compared to those who didn’t require translation [OR 0.41 (95% CI (0.25–0.66)]. We found that non‑Norwegian patients experience a higher symptom burden compared to Norwegian. We found that both non‑Norwegians and patient in need of translator were to a greater extent recommended treatment in primary health care. The proportion of non‑Norwegians patients receiving multidisciplinary treatment was similar to Norwegians, but those needing a translator were less likely to receive such treatment.

• Vagle, Markus; Dalen-Lorentsen, Torstein; Moksnes, Håvard; Harøy, Joar; Bjørneboe, John Andreas & Andersen, Thor Einar (2023). Physical Performance Profiles in Norwegian Premier League Female Football: A Descriptive Study. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(7), p. 695–703. doi: 10.1123/ijspp.2022-0360. Full text in Research Archive Show summary

  Purpose: To map anthropometric and physical performance profiles in Norwegian premier league female football players. Methods: During preseason, the physical qualities of 107 players were tested on Keiser leg press, countermovement jump, 40-meter sprint, and agility. Descriptive statistics were presented as mean (SD) and median [interquartile range]. Pearson correlations analyses were made for all performance tests, and results presented as R value with 95% CIs. Results: The female players were 22 (4) years of age, stature 169.0 (6.2) cm, body weight 65.3 (6.7) kg; force 2122 (312) N, power 1090 (140) W, sprint 40 m 5.75 (0.21) seconds, agility dominant 10.18 (0.32) seconds, nondominant 10.27 (0.31) seconds, and countermovement jump 32.6 (4.1) cm. Outfield players were faster and more agile than goalkeepers, a difference of 40 m, agility of dominant, and nondominant leg, respectively: 0.20 [0.09–0.32], 0.37 [0.21–0.54], and 0.28 [0.12–45]; P < .001. Goalkeepers and central defenders were taller and heavier compared with fullbacks, central midfielders, and wide midfielders (P ranging from <.02). A difference was found between dominant and nondominant legs for the agility test, showing that players are faster when changing direction with the dominant leg. Conclusions: Our study presents anthropometric and physical performance profiles of Norwegian premier league female football players. We found no difference for the physical qualities strength, power, sprint, agility, and countermovement jump between any outfield playing positions in female premier league players. There was a difference between outfield players and goalkeepers for sprint and agility.

• Bjørneboe, John Andreas; Heen, Anders; Borud, Einar Kristian; Bahr, Roald; Clarsen, Benjamin Matthew & Norheim, Arne Johan (2022). Introducing a new method to record injuries during military training: a prospective study among 296 young Norwegian conscripts. BMJ Military Health. ISSN 2633-3767. doi: 10.1136/bmjmilitary-2022-002088. Full text in Research Archive Show summary

  Introduction: Most epidemiological studies in the field of military medicine have been based on data from medical records and registries. The aims of this study were to test a self-reporting injury surveillance system commonly used in sports medicine in a military setting, and to describe the injury pattern among Norwegian army conscripts during a period of military training. Method: A total of 296 conscripts in His Majesty the King’s Guard were asked to report all injuries each week for 12 weeks, using a modification of the Oslo Sports Trauma Research Center Questionnaire on Health Problems (OSTRC-H2). We recorded all injuries irrespective of their need for medical attention or consequences for military participation. In addition, we retrieved data on injuries recorded by military physicians in the medical record from the Norwegian Armed Forces Health Register. Results: The mean weekly response rate was 74%. A total of 357 injuries were recorded, of which 82% were only captured through the OSTRC-H2 and 3% only in the medical records. The average weekly prevalence of injury was 28% (95% CI: 25% to 31%), and 10% (95% CI: 8% to 12%) experienced injuries with a substantial negative impact on training and performance. The greatest injury burden was caused by lower limb injuries, with knee and foot injuries as the predominant injury locations. Conclusion: The OSTRC-H2 is suitable for use in a military setting and records substantially more injuries than the standard medical record. The prevalence of injuries among conscripts is high and comparable with many elite sports.

• Dalen-Lorentsen, Torstein; Andersen, Thor Einar; Thorbjørnsen, Christian; Brown, Michael; Tovi, David & Braastad, Anders [Show all 11 contributors for this article] (2022). Injury characteristics in Norwegian male professional football: A comparison between a regular season and a season in the pandemic. Frontiers in Sports and Active Living. 4. doi: 10.3389/fspor.2022.915581. Full text in Research Archive Show summary

  The Coronavirus Disease-19 (COVID-19) pandemic forced the Norwegian male premier league football season to reschedule, reducing the fixture calendar substantially. Previous research has shown that a congested match schedule can affect injury rates in professional football. Therefore, we aimed to investigate whether the Norwegian premier league teams suffered more injuries in the more match congested 2020 season than in the regular 2019-season. We invited all teams having participated in both seasons to export their injury data. Only teams that used the same medical staff to register injuries in both seasons were included, and to maximize data comparability between seasons, we applied a time-loss injury definition only. Seven of 13 teams agreed to participate and exported their injury data. Both seasons had 30 game weeks, but the 2020 season was 57 days shorter than the 2019 season. The match injury incidence did not differ significantly [incidence rate ratio 0.76 (0.48–1.20; p = 0.24) in the 2020 season compared to the 2019 season. Furthermore, we found no differences in the number of injuries, days lost to injury, matches missed to injury, or injury severity. We could not detect any differences between the two seasons, suggesting the congested match calendar combined with the safety measures in the 2020 season can be a safe alternative in future seasons.

• Vagle, Markus; Dalen-Lorentsen, Torstein; Moksnes, Håvard; Harøy, Joar; Bjørneboe, John Andreas & Andersen, Thor Einar (2021). Fysisk prestasjonsevne blant norske elite kvinnefotballspillere - en deskriptiv studie. In Nyheim, Kurt Tomas (Eds.), Book of Abstract - Idrettsmedisinsk høstkongress 2021. NIMF. p. 9–9. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Ranvik, Andreas M.; Bjørneboe, John Andreas; Clarsen, Benjamin Matthew & Andersen, Thor Einar (2021). Facilitators and barriers for implementation of a load management intervention in football. BMJ Open sport & exercise medicine. 7(2), p. 1–9. doi: 10.1136/bmjsem-2021-001046. Full text in Research Archive Show summary

  Background: In a recent randomised controlled trial, we found that a commonly used training load management approach was not effective in preventing injuries and illnesses in Norwegian elite youth footballers. Aim: To investigate players’ and coaches’ barriers and facilitators to a load management approach to prevent injuries and illnesses and their attitudes and beliefs of load management and injuries and illnesses in general. Methods: We asked players and coaches about their views on injury risk in football, the benefits and limitations of load management in general and implementation of load management in football. The questionnaires used were based on similar studies using the Reach, Effectiveness, Adoption, Implementation and Maintenance framework. Results: We recorded answers from 250 players and 17 coaches. Most players (88%) reported that scientific evidence showing improved performance from the intervention measures is a key facilitator to completing the intervention. Similarly, coaches reported that the most important facilitator was scientific evidence that the preventive measures were effective (100%). Players reported that the coach’s attitude to preventive measures was important (86%), and similarly, 88% of coaches reported that the player’s attitude was important. Conclusions: By having a mutual positive attitude towards the intervention, players and coaches can positively contribute to each other’s motivation and compliance. Both players and coaches reported scientific evidence for load management having injury-preventive and performance-enhancing effect and being time efficient as important facilitators.

• Dalen-Lorentsen, Torstein; Andersen, Thor Einar; Bjørneboe, John Andreas; Vagle, Markus; Martin, Kevin Nordanger & Kleppen, Michael [Show all 8 contributors for this article] (2021). A Cherry, Ripe for Picking: The Relationship Between the Acute-Chronic Workload Ratio and Health Problems. Journal of Orthopaedic and Sports Physical Therapy. ISSN 0190-6011. 51(4), p. 162–173. doi: 10.2519/jospt.2021.9893. Full text in Research Archive Show summary

  Objective: To investigate whether the relationship between the acute-chronic workload ratio (ACWR) and health problems varies when different methodological approaches are used to quantify it. Design: Prospective cohort study. Methods: An online questionnaire was used to collect daily health and training information from 86 elite youth footballers for 105 days. The relationship between players' training load and health was analyzed using a range of different definitions of ACWR and health problems. We used 21-day and 28-day chronic periods, coupled and uncoupled calculations, and the exponentially weighted moving average and rolling average. Acute-chronic workload ratio data were categorized as low, medium, or high, using predefined categories and z scores. We compared medium to high, medium to low, and low to high categories. The outcome was defined in 3 ways: “all health problems,” “all injuries,” and “new noncontact injuries.” We performed random-effects logistic regression analyses of all combinations, for a total of 108 analyses. Results: We recorded 6250 athlete-days and 196 health problems. Of the 108 analyses performed, 23 (21%) identified a statistically significant (P<.05) association between the ACWR and health problems. A greater proportion of significant associations were identified when using an exponentially weighted moving average (44% of analyses), when comparing low to high categories (33%), and when using the “all health problems” definition (33%). Conclusion: The relationship between the ACWR and health problems was dependent on methodological approach.

• Dalen-Lorentsen, Torstein; Bjørneboe, John Andreas; Clarsen, Benjamin Matthew; Vagle, Markus; Fagerland, Morten & Andersen, Thor Einar (2020). Does load management using the acute:chronic workload ratio prevent health problems? A cluster randomised trial of 482 elite youth footballers of both sexes. British Journal of Sports Medicine. ISSN 0306-3674. 55(2), p. 108–114. doi: 10.1136/bjsports-2020-103003. Full text in Research Archive Show summary

  Background: The acute:chronic workload ratio (ACWR) is commonly used to manage training load in sports, particularly to reduce injury risk. However, despite its extensive application as a prevention intervention, the effectiveness of load management using ACWR has never been evaluated in an experimental study. Aim: To evaluate the effectiveness of a load management intervention designed to reduce the prevalence of health problems among elite youth football players of both sexes. Methods: We cluster-randomised 34 elite youth football teams (16 females, 18 males) to an intervention group (18 teams) and a control group (16 teams). Intervention group coaches planned all training based on published ACWR load management principles using a commercially available athlete management system for a complete 10-month season. Control group coaches continued to plan training as normal. The prevalence of health problems was measured monthly in both groups using the Oslo Sports Trauma Research Centre Questionnaire on Health Problems. Results: The between-group difference in health problem prevalence (primary outcome) was 1.8%-points (−4.1 to 7.7 %-points; p=0.55) with no reduction in the likelihood of reporting a health problem in the intervention group (relative risk 1.01 (95% CI 0.91 to 1.12); p=0.84) compared with the control group. Conclusions: We observed no between-group difference, suggesting that this specific load management intervention was not successful in preventing health problems in elite youth footballers.

• Kristenson, Karolina; Bjørneboe, John Andreas; Waldén, Markus; Ekstrand, Jan; Andersen, Thor Einar & Hägglund, Martin (2016). No association between surface shifts and time-loss overuse injury risk in male professional football. Journal of Science and Medicine in Sport. ISSN 1440-2440. 19(3), p. 218–221. doi: 10.1016/j.jsams.2015.06.001. Full text in Research Archive Show summary

  Objectives: To investigate frequent surface shifts and match play on an unaccustomed surface as potential risk factors for injury in Scandinavian male professional football. Design: Prospective cohort study. Methods: Thirty two top-division clubs (16 Swedish, 16 Norwegian) were followed during seasons 2010 and 2011. The influence from (1) number of surface shifts (between artificial turf and grass) during five-match sequences, and (2) match play on an unaccustomed surface (other surface than on the home venue) on subsequent overuse injury risk was evaluated with generalized estimating equations (GEE). GEE results are presented with risk ratios and 95% confidence interval (CI). Injury rate was expressed as time loss injuries/1000 h, and compared between groups with a rate ratio and 95% CI. Results: No association was found between the number of surface shifts and subsequent overuse injury risk (risk ratio 1.01, 95% CI 0.91–1.12). Furthermore, no difference was seen in subsequent overuse injury risk after match play on unaccustomed compared with accustomed surface (risk ratio 1.04, 95% CI 0.78–1.38). Grass clubs (grass installed at home venue) had a lower match injury rate when playing away matches on artificial turf compared with away matches on grass (rate ratio 0.66, 95% CI 0.40–0.89). Conclusions: This study showed no association between surface shifts or playing matches on an unaccustomed surface and time-loss injury risk in professional football, suggesting that clubs and players can cope with such surface transitions.

• Bjørneboe, John Andreas; Kristenson, Karolina; Waldén, Markus; Bengtsson, Håkan; Ekstrand, Jan & Hägglund, Martin [Show all 8 contributors for this article] (2016). Role of illness in male professional football: not a major contributor to time loss. British Journal of Sports Medicine. ISSN 0306-3674. 50(11), p. 699–702. doi: 10.1136/bjsports-2015-095921. Full text in Research Archive Show summary

  Background: There are limited data on the nature, type and incidence of illness in football. Previous studies indicate that gastrointestinal and respiratory tract illnesses are most common. Aim: To describe the incidence and burden of illness in male professional football. Methods: Over the 4-year study period, 2011–2014, 73 professional football teams in Europe participated, with a total of 1 261 367 player-days recorded. All time-loss illnesses were recorded by the medical staff of each club. A recordable illness episode was any physical or psychological symptom (not related to injury) that resulted in the player being unable to participate fully in training or match play. Results: A total of 1914 illness episodes were recorded. The illness incidence was 1.5 per 1000 player-days, meaning that, on average, a player experienced an illness episode every second season, with a median of 3 days absence per illness episode. Severe illness (absence >4 weeks) constituted 2% of all illnesses. Respiratory tract illness was the most common (58%), followed by gastrointestinal illness (38%). Respiratory tract illness, gastrointestinal illness and cardiovascular illness caused the highest illness burden. Conclusions: The illness incidence among male professional football players is low compared with the injury incidence. We found that the highest illness burden was caused by illness to the respiratory tract, gastrointestinal tract and cardiovascular system.

• Kristenson, Karolina; Bjørneboe, John Andreas; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hägglund, Martin (2016). Injuries in male professional football: A prospective comparison between individual and team-based exposure registration. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 26(10), p. 1225–1232. doi: 10.1111/sms.12551. Full text in Research Archive Show summary

  Methodological considerations of football injury epidemiology have only scarcely been described. The aim of this study was to evaluate the inter-rater agreement in injury capture rate and injury categorization for data registered in two different prospective injury surveillance audits studying the same two Norwegian male professional football clubs for two consecutive seasons, 2008–2009. One audit used team-based exposure (TBE) recording and the other individual-based exposure (IBE). The number of injuries recorded and corresponding injury rates (injuries/1000 h exposure) were compared between audits. Cohen's kappa and prevalence-adjusted bias-adjusted kappa (PABAK) coefficients were calculated for injury variables. Of 323 injuries included, the IBE audit captured 318 (overall capture rate 98.5%, training 98.9%, match 97.8%) and the TBE audit 303 injuries (overall capture rate 93.8%, training 91.4%, match 97.1%). Agreement analysis showed kappa and PABAK coefficients regarded as almost perfect (> 0.81) for 8 of 9 injury variables, and substantial (ƙ 0.75) for the variable injury severity. In conclusion, the capture rate for training injuries was slightly higher with IBE recording, and inter-agreement in injury categorization was very high.

• Waldén, Markus; Krosshaug, Tron; Bjørneboe, John Andreas; Andersen, Thor Einar; Faul, Oliver & Hägglund, Martin (2015). Three distinct mechanisms predominate in non-contact anterior cruciate ligament injuries in male professional football players: a systematic video analysis of 39 cases. British Journal of Sports Medicine. ISSN 0306-3674. 49(22), p. 1452–1460. doi: 10.1136/bjsports-2014-094573. Full text in Research Archive Show summary

  Background: Current knowledge on anterior cruciate ligament (ACL) injury mechanisms in male football players is limited. Aim: To describe ACL injury mechanisms in male professional football players using systematic video analysis. Methods: We assessed videos from 39 complete ACL tears recorded via prospective professional football injury surveillance between 2001 and 2011. Five analysts independently reviewed all videos to estimate the time of initial foot contact with the ground and the time of ACL tear. We then analysed all videos according to a structured format describing the injury circumstances and lower limb joint biomechanics. Results: Twenty-five injuries were non-contact, eight indirect contact and six direct contact injuries. We identified three main categories of non-contact and indirect contact injury situations: (1) pressing (n=11), (2) re-gaining balance after kicking (n=5) and (3) landing after heading (n=5). The fourth main injury situation was direct contact with the injured leg or knee (n=6). Knee valgus was frequently seen in the main categories of non-contact and indirect contact playing situations (n=11), but a dynamic valgus collapse was infrequent (n=3). This was in contrast to the tackling-induced direct contact situations where a knee valgus collapse occurred in all cases (n=3). Conclusions: Eighty-five per cent of the ACL injuries in male professional football players resulted from non-contact or indirect contact mechanisms. The most common playing situation leading to injury was pressing followed by kicking and heading. Knee valgus was frequently seen regardless of the playing situation, but a dynamic valgus collapse was rare.

• Bjørneboe, John Andreas; Bahr, Roald & Andersen, Thor Einar (2014). Gradual increase in the risk of match injury in Norwegian male professional football: A 6-year prospective study. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 24(1), p. 189–196. doi: 10.1111/j.1600-0838.2012.01476.x. Full text in Research Archive Show summary

  The aim of this study was to monitor injury incidence and pattern in Norwegian male professional football over six consecutive seasons and compare the risk of injury between the preseason and competitive season. All time loss injuries were recorded by the medical staff of each club. In total, 2365 injuries were recorded. The incidence of acute injuries was 15.9/1000 match hours [95% confidence interval (CI): 14.9–16.8], 1.9/1000 training hours (95% CI: 1.7–2.0), and 1.4 (95% CI: 1.3–1.5) overuse injuries/1000 h. A linear regression model found an annual increase of 1.06 acute match injuries/1000 h (95% CI: 0.40–1.73), corresponding to a total increase of 49% during the 6-year study period. When accounting for interteam variation and clustering effects using a general estimating equation model, the increase in injury incidence was 0.92 (95% CI: −0.11–1.95, P = 0.083). No difference in the risk of acute match injuries (rate ratio (RR): 0.86, 95% CI: 0.73–1.01), acute training injuries (RR: 1.16, 95% CI: 0.99–1.36), or overuse injuries (RR: 1.04, 95% CI: 0.89–1.21) was observed between the preseason and competitive season. In conclusion, the overall risk of acute match injuries in Norwegian male professional football increased by 49% during the study period, although this increase was not fully consistent across teams. We detected no change in the risk of training and overuse injuries or any difference between the preseason and competitive season.

• Bjørneboe, John Andreas; Bahr, Roald & Andersen, Thor Einar (2014). Video analysis of situations with a high-risk for injury in Norwegian male professional football; a comparison between 2000 and 2010. British Journal of Sports Medicine. ISSN 0306-3674. 48(9), p. 774–778. doi: 10.1136/bjsports-2012-091856. Full text in Research Archive Show summary

  Background: A recent study from Norwegian male professional football found that the risk of acute match injuries increased from 2002 to 2007. Objective: To compare the incidence of incidents with a propensity for injury, from the 2000 season to the 2010 season in Norwegian male professional football using video analysis. Methods: We conducted a video analysis of incidents in Norwegian professional football. An incident was recorded if the match was interrupted by the referee, and the player lay down for more than 15 s, and appeared to be in pain or received medical treatment. We also conducted a video analysis of all player-to-player contact situations occurring during 30 randomly selected matches. Results: A total of 1287 incidents were identified during the two seasons. The corresponding rate of incidents was 74.4 (95% CI 67.3 to 81.5) in the 2000 season and 109.6 (95% CI 102.3 to 116.9) in the 2010 season, a significant increase from 2000 to 2010 (rate ratio 1.47, 95% CI 1.31 to 1.66). We observed a significantly higher rate of opponent-to-player contact and non-contact incidents in the 2010 season, but no change in the proportion of fouls or sanctions awarded by the referee. The rate of player-to-player contact situations in both heading and tackling duels was lower during the 2010 season. Conclusions: We found an increased rate of non-contact and opponent-to-player contact incidents in both heading and tackling duels in the 2010 season compared with 10 years earlier, even if there was no increase in the frequency of player-to-player contact situations.

• Kristenson, Karolina; Bjørneboe, John Andreas; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hagglund, Martin (2013). The Nordic Football Injury Audit : higher injury rates for professional football clubs with third-generation artificial turf at their home venue. British Journal of Sports Medicine. ISSN 0306-3674. 47(12), p. 775–781. doi: 10.1136/bjsports-2013-092266. Full text in Research Archive Show summary

  Background: Previously, no difference in acute injury rate has been found when playing football on artificial turf (AT) compared with natural grass (NG). Aim: To compare acute injury rates in professional football played on AT and NG at the individual player level; and to compare, at club level, acute and overuse injury rates between clubs that have AT at their home venue (AT clubs) and clubs that have NG (NG clubs). Methods: 32 clubs (AT, n=11; NG, n=21) in the male Swedish and Norwegian premier leagues were followed prospectively during the 2010 and 2011 seasons. Injury rate was expressed as the number of time loss injuries/ 1000 h and compared with rate ratio (RR) and 99% CI. Results: No statistically significant differences were found in acute injury rates on AT compared with NG during match play (RR 0.98, 99% CI 0.79 to 1.22) or training (RR 1.14, 99% CI 0.86 to 1.50) when analysing at the individual player level. When analysing at the club level, however, AT clubs had a significantly higher acute training injury rate (RR 1.31, 99% CI 1.04 to 1.63) and overuse injury rate (RR 1.38, 99% CI 1.14 to 1.65) compared with NG clubs. Conclusions: At the individual player level, no significant differences were found in acute injury rates when playing on AT compared with NG. However, clubs with AT at their home venue had higher rates of acute training injuries and overuse injuries compared with clubs that played home matches on NG.

• Bjørneboe, John Andreas; Bahr, Roald; Dvorak, Jiri & Andersen, Thor Einar (2013). Lower incidence of arm-to-head contact incidents with stricter interpretation of the Laws of the Game in Norwegian male professional football. British Journal of Sports Medicine. ISSN 0306-3674. 47(8), p. 508–514. doi: 10.1136/bjsports-2012-091522. Full text in Research Archive Show summary

  Background: Video analyses reveal that the rate of incidents with a propensity for injury caused by opponent-to-player contact has increased by about 50% from 2000 to 2010 in Norwegian male professional football. The aim of the study was to assess whether a stricter interpretation of the Laws of the Game (red cards for high elbows in heading duels and for late/two foot tackles) could reduce the potential for injuries in Norwegian male professional football. Methods: A preintervention/postintervention design was employed, where the rate of incidents and injuries from the 2010 season (pre) was compared to the 2011 season (post). An incident was recorded if the match was interrupted by the referee, and the player lay down for more than 15 s, and appeared to be in pain or received medical treatment. Time-loss injuries were recorded by the medical staff of each club. Results: A total of 1421 contact incidents were identified, corresponding to a rate of 92.7 (95% CI 86.0 to 99.4) in the 2010 season and 86.6 (95% CI 80.3 to 99.4) in the 2011 season, with no difference between the two season. We found a reduction in the incidence of total head incidents (rate ratio (RR) 0.81, 95% CI 0.67 to 0.99), and head-incidents caused by arm-to-head contact (RR 0.72, 95% CI 0.54 to 0.97). We found no difference in tackling characteristics or contact injury rate. Conclusions: We found no significant differences in the overall rate of incidents after the introduction of stricter rule enforcement. However, the rate of head and arm-to head incidents was lower in the 2011 season.

• Bjørneboe, John; Flørenes, Tonje Wåle; Bahr, Roald & Andersen, Thor Einar (2011). Injury surveillance in male professional football ; is medical staff reporting complete and accurate? Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 21(5), p. 713–720. doi: 10.1111/j.1600-0838.2009.01085.x. Full text in Research Archive Show summary

  Since the 2000 season, an injury surveillance system has been established to monitor injury risk and injury patterns in the Norwegian professional football league. The aim of this study was to assess the accuracy of routine injury registration performed by medical staff in professional football. The team medical staff completed injury registration forms on a monthly basis throughout the 2007 season (January–October). Players were interviewed at the end of the season (October/November) about all injuries that occurred from July through September. Thirteen of fourteen teams, 296 of 310 A-squad players were interviewed. An injury was recorded when a player was unable to take fully part in football training or match the day after injury. A total of 174 injuries were registered, 123 acute injuries and 51 overuse injuries. Of these, 141 were reported by medical staff and 122 by players. Eighty-nine injuries (51%) were registered using both methods, 52 (30%) by medical staff only and 33 (19%) by player interviews only. Prospective injury surveillance by team medical staff in Norwegian male professional football underestimates the incidence of time-loss injuries by at least one-fifth.

• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2010). Risk of injury on third-generation artificial turf in Norwegian professional football. British Journal of Sports Medicine. ISSN 0306-3674. 44(11), p. 794–798. doi: 10.1136/bjsm.2010.073783. Full text in Research Archive Show summary

  Background: Artificial turf is used extensively in both recreational and elite football in areas with difficult climatic conditions. Objective: To compare the risk for acute injuries between natural grass (NG) and third-generation artificial turf (3GAT) in male professional football. Study design: Prospective cohort study. Methods: All injuries sustained by players with a first-team contract were recorded by the medical staff of each club, from the 2004 throughout the 2007 season. An injury was registered if the player was unable to take fully part in football activity or match play. Results: A total of 668 match injuries, 526 on grass and 142 on artificial turf, were recorded. The overall acute match injury incidence was 17.1 (95% CI 15.8 to 18.4) per 1000 match hours; 17.0 (95% CI 15.6 to 18.5) on grass and 17.6 (95% CI 14.7 to 20.5) on artificial turf. Correspondingly, the incidence for training injuries was 1.8 (95% CI 1.6 to 2.0); 1.8 (95% CI 1.5 to 2.0) on grass and 1.9 (95% CI 1.5 to 2.2) on artificial turf respectively. No significant difference was observed in injury location, type or severity between turf types. Conclusion: No significant differences were detected in injury rate or pattern between 3GAT and NG in Norwegian male professional football.

View all works in NVA

• Bjørneboe, John Andreas (2025). The long-term consequences of head impacts in football. Full text in Research Archive
• Bjørneboe, John Andreas; Dahlén, Sara; Sandmo, Stian Bahr; Bache-Mathiesen, Lena Kristin & Andersen, Thor Einar (2025). Ingen økt risiko for nevrodegenerativ sykdom hos tidligere kvinnelige toppfotballspillere. Idrettsmedisinsk Høstkongress. p. 12–12. doi: https:/www.researchgate.net/publication/397709745_Ingen_okt_risiko_for_nevrodegenerativ_sykdom_hos_tidligere_kvinnelige_toppfotballspillere. Full text in Research Archive
• Dahlén, Sara; Bjørneboe, John Andreas; Sandmo, Stian Bahr; Bache-Mathiesen, Lena Kristin; Filipcik, Peter & Howe, Emilie Isager [Show all 12 contributors for this article] (2025). Brain health in female former top-level football players . Full text in Research Archive
• Bjørneboe, John Andreas & Dalen-Lorentsen, Torstein (2025). Forward together. British Journal of Sports Medicine. ISSN 0306-3674. 59(18), p. 1269–1269. doi: 10.1136/bjsports-2025-110705. Full text in Research Archive Show summary

  We are delighted to present the annual issue of the Norwegian Sports and Exercise Medicine Society in the British Journal of Sports Medicine. This year, we proudly embrace the slogan of the Oslo Sports Trauma Research Center’s (OSTRC) 25th anniversary conference: ‘25 Years of Protecting Athlete Health: Forward Together’. With over 350 participants, the conference was a tremendous success, highlighting advancements in sports injury and illness prevention over the past quarter century and exploring how we can collaboratively move forward. As emerging researchers in sports medicine, we are honoured to stand on the shoulders of giants, OSTRC founders Professor Roald Bahr and Professor Lars Engebretsen. This issue reflects key themes from the discussions held in Svolvær.

• Aars, Nils Abel; Brandseth, Oda Lekve; Bardal, Ingvild; Stevelink, Sharon; Sanatkar, Samineh & Trichet, Laurent Olivier [Show all 14 contributors for this article] (2025). Cohort profile: the Norwegian Neck and Back Registry (NNRR): a medical quality registry for patients with neck and back complaints. BMJ Open. 15(3). doi: 10.1136/bmjopen-2024-096992. Full text in Research Archive
• Dahlén, Sara; Bjørneboe, John Andreas; Sandmo, Stian Bahr; Bache-Mathiesen, Lena Kristin; Filipcik, Peter & Howe, Emilie Isager [Show all 12 contributors for this article] (2025). Brain health in Norwegian female former top-level football players: a protocol for a longitudinal cohort study. doi: 10.1136/bmjopen-2024-092456. Full text in Research Archive
• Melås, Thea Morin; Bjørneboe, John Andreas; Juel, Niels Gunnar; Wefring, Maren Lunder; Skatteboe, Sigrid & Killingmo, Rikke Munk [Show all 14 contributors for this article] (2024). Self-management versus usual care for greater trochanteric pain syndrome: protocol for a randomized controlled trial with nested qualitative interviews (the HIPS trial). Full text in Research Archive
• Rasmussen, Mari Storli; Andelic, Nada; Selj, Joanna Nordhagen; Danielsen, Vilde Marie; Løvstad, Marianne & Howe, Emilie Isager [Show all 30 contributors for this article] (2024). Self-management support program delivered in the sub-acute phase after traumatic injury-study protocol for a pragmatic randomized controlled trial. Trials. 25(1), p. 639–639. doi: 10.1186/s13063-024-08492-0. Full text in Research Archive Show summary

  Background Traumatic injuries, defined as physical injuries with sudden onset, are a major cause of distress and disability, with far-reaching societal consequences. A significant proportion of trauma survivors report persistent symptoms and difficulties after the injury, and studies show unmet health care needs. Self-management programs delivered in the sub-acute phase after traumatic injuries are scarcely evaluated. The aim of the present study is to evaluate the effectiveness of a self-management program (SEMPO), delivered 3–4 months after moderate-to-severe traumatic injury. Methods This study protocol describes a pragmatic randomized controlled trial (RCT) with two classical RCT arms (intervention and control) and an explorative self-selection arm. 220 patients will be recruited from Oslo University Hospital, the largest Trauma Referral Centre in Norway. Patients aged 18–72 years residing in the south-east region of Norway, admitted to the Trauma Centre directly or within 72 h after having sustained a moderate to severe traumatic injury, defined as a New Injury Severity Score > 9, having at least 2 days hospital stay, and reporting injury-related symptoms and impairment at discharge from the acute hospital will be included. Patients will be randomly assigned to either a classical RCT randomization arm (intervention or control arm) or to a self-selection arm. In the randomization arm, participants are further randomized into intervention or control group. Participants allocated to the self-selection arm will choose to partake either in the intervention or control arm. The primary outcome is the level of self-efficacy in trauma coping assessed 6 months after completion of the intervention, with a similar time point for the control group. Secondary outcomes include symptom burden, physical functioning and disability, return to work and health care utilization, health-related quality of life, and communication competency. In addition, patients will be asked to nominate one domain-related measurement as their preferred outcome measure. Discussion This RCT will determine the effect of a self-management program tailored to patients with moderate to severe physical trauma, and the self-selection arm incorporates the potential influence of patient treatment preferences on intervention results. If the intervention proves effective, cost-effectiveness and cost-utility analyses will be performed and thereby provide important information for clinicians and policy makers. Trial registration The study is registered in Clinical Trials with the identifier: NCT06305819. Registered on March 05, 2004.

• Bjørneboe, John Andreas; Andersen, Thor Einar & Dahlén, Sara (2024). Brain health in female football players. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Bjørneboe, John Andreas; Harøy, Joar & Andersen, Thor Einar (2024). We stand with the players: a call to action for the football community. British Journal of Sports Medicine. ISSN 0306-3674. 58(12). doi: 10.1136/bjsports-2023-108041. Full text in Research Archive
• Bjørneboe, John Andreas & Dalen-Lorentsen, Torstein (2024). Riding towards better athlete health. British Journal of Sports Medicine. ISSN 0306-3674. 58(20). doi: 10.1136/bjsports-2024-109168. Full text in Research Archive
• Bjørneboe, John Andreas & Wangensteen, Arnlaug (2022). Show courage! British Journal of Sports Medicine. ISSN 0306-3674. 56(15), p. 829–830. doi: 10.1136/bjsports-2022-106026. Full text in Research Archive
• Bjørneboe, John Andreas & Wangensteen, Arnlaug (2021). No limits in the future of sports and exercise medicine! British Journal of Sports Medicine. ISSN 0306-3674. 55(19), p. 1061–1062. doi: 10.1136/bjsports-2021-104826. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Bjørneboe, John Andreas; Vagle, Markus; Clarsen, Benjamin Matthew; Fagerland, Morten & Andersen, Thor Einar (2021). Kan styring av treningsbelastning redusere helseproblemer? En cluster-randomisert kontrollert studie av 482 junior-elite fotballspillere av begge kjønn. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Andersen, Thor Einar; Thorbjørnsen, Christian; Brown, Michael; Tovi, David & Braastad, Anders [Show all 11 contributors for this article] (2021). Skadedata fra eliteserien i fotball: Er det forskjeller mellon en vanlig sesong og en sesong i pandemien? Full text in Research Archive
• Vagle, Markus; Dalen-Lorentsen, Torstein; Moksnes, Håvard; Harøy, Joar; Bjørneboe, John Andreas & Andersen, Thor Einar (2021). Physical performance profiles in elite female football: a descriptive study. Full text in Research Archive
• Andersen, Thor Einar & Bjørneboe, John Andreas (2018). The Experience from the Oslo Sports Trauma Research. In Musahl, Volker; Karlsson, Jon; Krutsch, Werner; Mandelbaum, Bert R.; Espregueira-Mendes, Joao & d'Hooghe, Pieter (Ed.), Return to Play in Football: An Evidence-based Approach. Springer. ISSN 9783662557129. p. 885–892. Full text in Research Archive
• Kleppen, Michael; Dalen-Lorentsen, Torstein; Vagle, Markus; Martin, Kevin Nordanger; Bjørneboe, John Andreas & Harøy, Joar [Show all 7 contributors for this article] (2018). Skadeinsidensen blant junior elite fotballspillere. Full text in Research Archive
• Bjørneboe, John Andreas (2014). Rule change can reduce potential injuries. Full text in Research Archive
• Ekstrand, Jan; Andersen, Thor Einar; Clarsen, Benjamin; Soligard, Torbjørn; Verheijen, Raymond & Bjørneboe, John Andreas [Show all 7 contributors for this article] (2014). Session: Prevention of football injuries at the elite level. Panel discussion. Full text in Research Archive
• Kristenson, Karolina; Bjørneboe, John Andreas; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hägglund, Martin (2014). The Nordic Football Injury Audit: higher injury rates for professional football clubs with third-generation artifi cial turf at their home venue. Full text in Research Archive
• Kristenson, Karolina; Bjørneboe, John Andreas; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hagglund, Martin (2014). The nordic football injury aduit - higher injury rates for professional football clubs with third-generation artificial turf at their home venue. British Journal of Sports Medicine. ISSN 0306-3674. 48(7), p. 621–621. Full text in Research Archive
• Bjørneboe, John Andreas (2014). Injury surveillance and prevention in male professional football. Full text in Research Archive
• Bjørneboe, John Andreas (2014). Injury surveillance and prevention in male professional football. Full text in Research Archive
• Bjørneboe, John Andreas (2014). Prevention of football injuries. Full text in Research Archive
• Bjørneboe, John Andreas; Kristenson, K; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hägglund, M (2013). Økt risiko for skade blant lag med kunstgress på hjemmebane i Allsvenskan og Tippeligaen. Norsk idrettsmedisin. ISSN 0806-9328. p. 20–20. Full text in Research Archive
• Bjørneboe, John Andreas; Bahr, Roald; Dvorak, Jiri & Andersen, Thor Einar (2013). Færre arm-mot-hode hendelser i tippeligaen etter innføring av strengere regelfortolkning. Norsk idrettsmedisin. ISSN 0806-9328. Full text in Research Archive
• Bjørneboe, John Andreas; Kristenson, K; Waldén, Markus; Andersen, Thor Einar; Ekstrand, Jan & Hägglund, M (2013). Økt risiko for skade blant lag med kunstgress på hjemmebane i Allsvenska og Tippeligaen. Full text in Research Archive
• Bjørneboe, John Andreas; Bahr, Roald; Dvorak, Jiri & Andersen, Thor Einar (2013). Færre arm-mot-hode hendelser i tippeligaen etter innføring av strengere regelfortolkning. Full text in Research Archive
• Bjørneboe, John Andreas (2013). Skaderisiko i Tippeligaen. Full text in Research Archive
• Bjørneboe, John Andreas (2013). Skaderisiko i Tippeligaen. Full text in Research Archive
• Bjørneboe, John (2012). Injuries in male professional football. Full text in Research Archive
• Bjørneboe, John (2011). Skadestatistikk i Tippeligaen. Full text in Research Archive
• Andersen, Thor Einar; Bjørneboe, John & Bahr, Roald (2011). Rule enforcement for late tackles and elbowing in Tippeligaen. Full text in Research Archive
• Flørenes, Tonje Wåle; Bjørneboe, John; Andersen, Thor Einar; Heir, Stig & Bahr, Roald (2011). What is more dangerous - football, skiing or snowboarding? Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2011). Risiko for skader i tippeligaen. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2011). Risiko for skader i tippeligaen. Norsk idrettsmedisin. ISSN 0806-9328. Full text in Research Archive
• Bjørneboe, John (2011). Rule enforcement for late tackles and elbowing in Tippeligaen - an intervention program. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2011). Risk of injury in Norwegian male professional football. Full text in Research Archive
• Andersen, Thor Einar; Bjørneboe, John & Bahr, Roald (2011). Rule enforcement for late tackles and elbowing in Tippeligaen. Full text in Research Archive
• Flørenes, Tonje Wåle; Bjørneboe, John; Andersen, Thor Einar; Heir, Stig & Bahr, Roald (2011). What is more dangerous - football, skiing or snowboarding? British Journal of Sports Medicine. ISSN 0306-3674. 45, p. 348–348. doi: 10.1136/bjsm.2011.080438.107. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2011). Risk of injury in Norwegian male professional football. British Journal of Sports Medicine. ISSN 0306-3674. 45, p. 336–337. doi: 10.1136/bjsm.2011.084038.75. Full text in Research Archive
• Bahr, Roald; Flørenes, Tonje W.; Bjørneboe, John; Andersen, Thor Einar & Heir, Stig (2010). What is more dagnerous - ski, snowboard or football? Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. p. 31–31. Full text in Research Archive
• Flørenes, Tonje W.; Bahr, Roald; Bjørneboe, John; Andersen, Thor Einar & Heir, Stig (2009). Hva er farligst - ski, snowborad eller fotball? Full text in Research Archive
• Flørenes, Tonje W.; Bjørneboe, John; Andersen, Thor Einar; Heir, Stig & Bahr, Roald (2009). Hva er farligst - ski, snowboard eller fotball? Norsk idrettsmedisin. ISSN 0806-9328. p. 18–18. Full text in Research Archive
• Bjørneboe, John (2009). Injury risk in male elite football (2002-08) - a preliminary summary. Full text in Research Archive
• Bjørneboe, John; Steffen, Kathrin & Soligard, Torbjørn (2008). Skaderisiko på kunstgress: erfaringer fra Norsk eliteserie, jentefotball og Norway Cup. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2008). INJURY SURVEILLANCE IN MALE NORWEGIAN PROFESSIONAL FOOTBALL: A METHODOLOGICAL STUDY. British Journal of Sports Medicine. ISSN 0306-3674. p. 494–494. Full text in Research Archive
• Bjørneboe, John; Andersen, Thor Einar & Bahr, Roald (2008). RISK OF INJURY ON ARTIFICIAL TURF IN ELITE FOOTBALL. British Journal of Sports Medicine. ISSN 0306-3674. p. 494–494. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2008). Injury surveillance in male Norwegian professional football - a methodological study. Full text in Research Archive
• Bahr, Roald; Bjørneboe, John & Andersen, Thor Einar (2008). Injury surveillance in male Norwegian professional football - a methodological study. Norsk idrettsmedisin. ISSN 0806-9328. p. 17–17. Full text in Research Archive
• Bjørneboe, John; Bahr, Roald & Andersen, Thor Einar (2008). Injury surveillance in male Norwegian professional football - a methodological study. Full text in Research Archive
• Bjørneboe, John (2008). Injury Surveillance in male Norwegian professional football - a methodological study. Full text in Research Archive
• Bjørneboe, John (2008). The 11+ - A comprehensive warm-up program to pervent injuries in female youth football. Full text in Research Archive
• Bahr, Roald; Bjørneboe, John & Andersen, Thor Einar (2008). Risk of injury on artificial turf in norwegian professional football. Full text in Research Archive
• Bjørneboe, John; Andersen, Thor Einar & Bahr, Roald (2008). Risk of injury on artificial turf in elite football. Full text in Research Archive
• Bjørneboe, John (2007). Tippeligaen - a compliance study. Full text in Research Archive
• Bjørneboe, John (2007). Injury registration in Norwegian male elite football. Full text in Research Archive
• Andersen, Thor Einar; Bahr, Roald & Bjørneboe, John (2006). Risiko for skader på kunstgressdekke i fotball. Norsk idrettsmedisin. ISSN 0806-9328. p. 17–17. Full text in Research Archive
• Andersen, Thor Einar; Bjørneboe, John & Bahr, Roald (2006). Skaderisiko i sesongoppkjøring versus konkurransesong. Norsk idrettsmedisin. ISSN 0806-9328. p. 17–17. Full text in Research Archive
• Bahr, Roald; Andersen, Thor Einar & Bjørneboe, John (2006). Skaderisiko i sesongoppkjøring versus konkurransesesong. Full text in Research Archive
• Andersen, Thor Einar; Bjørneboe, John & Bahr, Roald (2006). Risiko for skader på kunstgressdekke i fotball. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Bjørneboe, John Andreas; Vagle, Markus; Clarsen, Benjamin Matthew; Fagerland, Morten & Andersen, Thor Einar (2021). Kan styring av treningsbelastning redusere helseproblemer? En cluster-randomisert kontrollert studie av 482 junior-elite fotballspillere av begge kjønn. NIMF. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Andersen, Thor Einar; Thorbjørnsen, Christian; Brown, Michael; Tovi, David & Braastad, Anders [Show all 11 contributors for this article] (2021). Skadedata fra eliteserien i fotball -er det forskjeller mellom en vanlig sesong og en sesong i pandemien. NIMF. Full text in Research Archive
• Dalen-Lorentsen, Torstein; Andersen, Thor Einar; Clarsen, Benjamin Matthew & Bjørneboe, John Andreas (2021). Training load and health problems in football: More complex than we first thought? Norges idrettshøgskole. ISSN 9788250205970. Full text in Research Archive Show summary

  Background: Health problems are prevalent in football, and in both elite youth and professional football, players are expected to sustain several health problems per season. Also, at any given time of the season, the prevalence of health problems (both injuries and illnesses) exceeds 40% among elite youth players. Training load has recently emerged as a potential risk factor for health problems in football; subsequently, many teams, particularly those at an elite level, attempt to manage players’ training loads as a preventative measure to mitigate health problem risk. However, the evidence supporting this practice is limited, and its effectiveness is never tested. Therefore, this dissertation aims to improve our understanding of the relationship between training load and health problems and to guide preventative efforts. Methods: All studies were performed on Norwegian football players and coahces, Papers I, II and III in elite youth (U19 age category) and Paper IV in professional football. In the first study (Paper I), we registered daily training load and health data to assess methodological issues in the relationship between the Acute:chronic workload ratio (ACWR) and health problems. The second study (Paper II) was a cluster-randomised trial that assessed the effectiveness of a load management programme on health problem prevention. We followed 482 players for a full season, registering their monthly health problem prevalence. In Paper III, we surveyed 250 of the players included in Paper II about their attitudes, beliefs and experiences of load management and health problems. In Paper IV, we assessed the injury characteristics of two different football seasons in the Norwegian premier league. This explorative descriptive study collected injury data from eight teams participating in the 2019 and 2020 seasons. Main results: In Paper I, we found 24 (22%) significant associations between ACWR and health problems among the 108 analyses performed. These were spread across various methodological combinations. We did not observe any patterns of combinations that substantially increased the chance of a significant association. There was a considerable variation in the size and precision of the estimated strength of the association. In Paper II, the average prevalence of health problems was 65.7% (61.1% to 70.2%) in the intervention group and 63.8% (60.0% to 67.7%) in the control group. The prevalence was 1.8%-points (-4.1 to 7.7%-points; P=0.55) higher in the intervention group, and there was no reduction in the likelihood of reporting a health problem in the intervention group (Relative Risk, RR 1.01 (95% CI 0.91 to 1.12 ); P=0.84). In Paper III, we found that most players (88%) think scientific evidence for improved performance is a key facilitator to implementation. Similarly, the coaches reported that the most crucial facilitator was scientific evidence that the preventive measures were effective (100%). Players reported that the coach’s attitude to preventive measures was important (86%), and similarly, 88% of coaches reported that the player’s attitude was important. In Paper IV, the match incidence was 7.23 per 1000h lower in 2020 (22.82 per 1000h; CI 18.07 to 28.44; Incidence Rate Ratio; IRR 0.76) than in 2019 (30.05 per 1000h; CI 24.55 to 36.41); however, this was not a significant difference. There were no differences in either availability, severity or injury burden across the two seasons. Conclusion: Based on our findings, we conclude that the relationship between ACWR and health problems is highly affected by the methodological approach, which can lead to p-hacking and cherry-picking of results. Future training load studies should pre-register their definitions, hypotheses, models and report all performed analyses' results. Furthermore, managing training loads using ACWR in a onesize-fits-all approach does not appear to prevent health problems in elite youth football. When implementing future health problem preventive measures, practitioners and researchers should focus on time-efficient interventions and create buy-in from club and federation stakeholders as well as coaches and players by focusing on both performance and prevention. Finally, we found no differences in injuries comparing a match-congested season with a regular one, suggesting a congested season can be a safe alternative.

• Bjørneboe, John Andreas; Andersen, Thor Einar & Bahr, Roald (2014). Injury surveillance and prevention in male professional football. Universitetet i Oslo. Full text in Research Archive
• Eriksen, Even Eide; Bjørneboe, John Andreas & Andersen, Thor Einar (2013). Skader og sykdom hos unge norske elitefotballspillere – en prospektiv kohortestudie. Norges idrettshøgskole. Full text in Research Archive
• Andersen, Thor Einar & Bjørneboe, John Andreas (2010). Injuries in professional football. Universitetet i Oslo. Full text in Research Archive

View all works in NVA