Pain is the most burdensome global health issue causing disability at present . Impacts on individuals and society are diverse and far-reaching , . Pain is highly prevalent and experienced by individuals of all ages. Data from epidemiological studies have shown that 67% of individuals aged 15 years and over , and 72% of adults aged 50 years and over , have experienced recent bodily pain, while population-based rates of chronic pain range from 17% to 47% , .
While the problem of pain has been highlighted , it is important to contextualise this focus with an understanding of how healthy populations present. Pain has been associated with poor self-reported health and quality of life , , however not all individuals with pain experience high levels of disability. A 2016 systematic review reported the prevalence of chronic pain in the UK to be 43%, of which 10%–14% was classified as moderately/severely disabling . Accordingly, the remaining 29%–33% of individuals presumably reported chronic pain yet experienced minimal or no disability. Further analysis of how prevalent pain is in people who perceive themselves as healthy would contribute to our understanding of the burden of pain.
The manifestation and impacts of pain vary greatly due to interactions between neurobiological, environmental, cognitive and emotional factors , , , . Knowledge of pain characteristics among the healthy population or those with minimal physical disability or psychological impact could hold important insights to inform clinical practice and research. However, insufficient attention has been paid to this population. In one of the few studies on profiles of healthy people, Jones et al.  found that only one in six persons in their population-based study (n=2,260) did not report musculoskeletal pain across a 4-year period, and that those without pain had lower levels of psychological distress and better quality sleep compared to those who developed pain. This highlights the importance of broader health factors in influencing musculoskeletal health. To this end, investigating biopsychosocial characteristics of individuals who report pain yet suffer minimal pain-related disability could yield key discoveries regarding the (potentially modifiable) factors which contribute to maintaining a functional state despite pain, providing opportunities for prevention and treatment targets. Therefore, the primary aim of this study was to investigate the prevalence of pain (recent/chronic), among a sample of 1,000 healthy children and adults. A further aim was to compare psychosocial and physical characteristics between healthy adults with and without recent/chronic pain.
Data for this study were from the 1,000 Norms Project, a cross-sectional observational study investigating self-reported outcomes and physical performance in 1,000 healthy individuals aged 3–101 years, stratified by age and gender . Participants were recruited via online, paper and face-to-face advertising methods through local council and state government groups; community and sporting groups; schools and tertiary education institutions; and aged care independent living facilities. A structured convenience sampling approach targeting the Greater Sydney metropolitan area, which accounts for one-fifth of Australia’s population , was employed. Due to Australian privacy legislation and the high proportion of “mobile-phone-only” Australian households, random sampling was not feasible . Ethical approval for the 1,000 Norms Project was granted by the institutional Ethics Committee (HREC 2013/640).
Participants were eligible if they considered themselves healthy by self-report and had no major physical disability. Pain minor medical conditions (e.g. history of musculoskeletal injury) were not included or excluded as such, rather the individual’s physical functioning was taken into account. Potential participants were asked the following questions:
“Do you consider yourself healthy for your age?”
“Are you able to participate in normal daily activities with respect to your age?”
Individuals who responded “yes” to both questions were screened for the following exclusion criteria:
Inability to follow age-appropriate instructions in English;
Self-reported medical conditions or factors known to affect function in daily activities, including: infectious or inflammatory arthropathies; severe musculoskeletal disorders (e.g. end-stage osteoarthritis); history of joint replacement or other major surgery; diabetes; malignant cancers; demyelinating, inflammatory or degenerative neurological conditions; severe cardiac or pulmonary disease; pregnancy; body mass index (BMI) ≥40 kg/m2 (Class III obesity) or mobility limitations necessitating dependence on mobility aids .
Ethnicity of participants was collected according to the Australian Standard Classification of Cultural and Ethnic Groups  and was classified into one of three groups using participants’ country of birth: British/European, Aboriginal/Torres Strait Islander or “other” (Asian/American/African/Middle-Eastern). Socio-economic status was assessed using the socio-economic indexes for areas (index of relative socio-economic advantage and disadvantage), ranking Australian residential postcodes in terms of relative advantage or disadvantage on a percentile score from 1 (most disadvantaged) to 100 (most advantaged) .
2.2 Pain prevalence
All participants were asked to rank the intensity of recent bodily (generalised) pain they had experienced in the past 4 weeks on a six-point scale from “none” to “very severe”, based on the 36-Item Short Form Health Survey  as used by the Australian Bureau of Statistics . Presence of chronic pain, defined as pain experienced every day for 3 months in the previous 6 months, was also assessed in all participants using a single-item “Yes/No” question . Neither of these two items were body site-specific, and for children aged 3–10 years the parent/caregiver completed both questions.
2.3 Psychosocial characteristics
Psychosocial characteristics were collected in adults (18+ years). Mental health was evaluated using the 35-item Assessment of Quality of Life-8 Dimension (AQoL-8D) utility instrument . The AQoL-8D assesses eight dimensions and generates two super-dimensions (mental and physical) as well as a global “utility”, scored from 0 (death-equivalent) to 1.00 (best health state). Data for the mental super-dimension (combining “mental health”, “self-worth”, “relationships”, “happiness” and “coping” dimensions) were analysed. To investigate sleep difficulties, responses for the AQoL-8D question regarding sleep problems in the past week were re-coded to a binary variable as “no” (never/almost never) or “yes” (sometimes/often/all the time). Although the validity of this single-item question is unknown, a similar item ranking sleep quality from 0 to 10 has demonstrated sound validity . Self-efficacy was assessed using the Generalized Self-Efficacy Scale, an eight-item Likert-scale questionnaire . Responses were summed to give a score from 5 (lowest) to 40 (best self-efficacy).
2.4 Physical characteristics
Self-reported physical activity level was measured in adults using the International Physical Activity Questionnaire (IPAQ)-long (18–69 years)  and the IPAQ-elderly (70–101 years) . A categorical score of low, moderate or high physical activity was allocated and re-coded to a binary variable indicating “low/moderate” or “high” physical activity level . A standardised protocol was used to collect physical measures . BMI in adults (18+ years) was recorded and classified as “underweight/normal weight” (<25.0) or “overweight/obese” (≥25.0) using established cut-off scores . The 6-min walk test was used to measure walking endurance . Participants walked as quickly as possible for 6 min, generating a 6-min walk distance (m). Sit-to-stand ability was evaluated using the 30-s chair stand test, whereby the number of full sit-to-stands performed in 30 s was recorded . The timed up and down stairs test was used to assess stair-climbing performance. Participants were asked to ascend and descend a flight of stairs as quickly and safely as possible (s) . Data were scaled to leg length for the 6-min walk and timed up and down stairs tests . Two experienced physiotherapists (J. N. B and M. J. M) conducted the physical assessments, with excellent inter-rater reliability (ICC2,1=0.94–0.98) established through pilot testing (n=10, age range 6–67 years).
2.5 Statistical analysis
Data were managed using REDCap (Research Electronic Data Capture, Nashville, TN, USA) . SPSS for Windows 22.0 software package was used for statistical analyses (IBM SPSS Inc., Chicago, IL, USA). Cases with missing data were removed from analyses. To compare adults with and without recent pain, responses to the recent bodily pain question were coded into two groups: “none” and “mild/moderate/severe”. To examine differences in demographic, psychosocial and physical characteristics between adults with and without (recent/chronic) pain, Pearson χ2 tests with continuity correction were used for binary variables and independent sample t-tests for continuous variables. Effect sizes for continuous data for the psychosocial and physical measures were calculated using Cohen’s d where results were statistically different between groups (p<0.05).
The ethnic profile of the 1,000 participants was similar to the Australian population, however participants were from more socio-economically advantaged areas (Table 1). A similar proportion of children aged 3–17 years were overweight/obese compared to Australian children aged 2–17 years, although a lower proportion of adult participants were overweight/obese compared to Australian adults.
3.1 Pain prevalence
Sixty-six percent of all participants (n=657) had experienced some pain within the past 4 weeks. Seventy-two percent of adults (n=528) and 48.5% (n=129) of children had experienced recent pain, although most (80.3% of adults, 86.8% of children) rated their pain as very mild/mild (Table 2). Moderate/severe pain was reported by 15.6% of adult males and 12.8% of adult females aged 18–101 years, and by 4.5% of paediatric males and 8.3% of paediatric females. Generalised pain was lowest among children, as 67% (n=47) of boys and 56% (n=39) of girls aged 3–9 years had experienced no pain in the past 4 weeks, while moderate/severe pain was highest for adults aged 40–49, 70–79 and 80+ years (Fig. 1).
Chronic pain was reported by 11.7% (n=117) of all participants, including 14.8% (n=108) of adults and 3.4% (n=2) of children (Table 2). Chronic pain was lowest among children aged 3–9 years (1%, n=1 males; 4%, n=3 females), and highest among older males aged 60–69, 70–79 and 80–101 years (22%, n=11 for each group) and among older females aged 80+ years (22%, n=11) (Fig. 2). No participants reported “very severe” pain, and there were no differences in pain intensity or chronic pain between genders or among ethnic backgrounds (p>0.05).
3.2 Psychosocial and physical characteristics of adults with and without pain
Adults who had recently experienced pain (mild/moderate/severe) (n=528) were more likely to be overweight/obese and report sleep difficulties, reported lower mental super dimension and self-efficacy scores, and had lower performance on the 30-s chair stand test, compared to adults with no pain (n=204, p<0.05) (Table 3). Effect sizes for the differences in mental health, self-efficacy and physical performance were modest (Cohen’s d=0.16–0.39) and therefore unlikely clinically significant. There were no differences in physical activity levels (p>0.05).
Adults who had experienced chronic pain in the past 6 months (n=108) were older, were more likely to be overweight/obese, reported lower mental super dimension scores and had lower performance on the 6-min walk, 30-s chair stand and timed up and down stairs tests, compared to adults without chronic pain (n=624, p<0.05) (Table 4). Again, effect sizes were modest (Cohen’s d=0.25–0.40). Levels of self-efficacy were similar between adults with and without chronic pain, and there was no difference in the proportion of individuals with sleep difficulties or physical activity levels across these groups (p>0.05).
Pain was common in this sample of 1,000 healthy individuals, with 72% of adults and 48% of children experiencing recent pain, although most rated their pain as mild. Recent pain was linked with higher rates of overweight/obesity and sleep problems, and lower mental health, self-efficacy and sit-to-stand performance. Chronic pain was reported by 14% of adults and 3% of children. Adults with chronic pain were older and more likely to be overweight/obese, reported lower mental health and had lower physical performance compared to adults without pain. However, differences in psychosocial and physical characteristics between adults with and without pain (recent/chronic) were unlikely clinically significant.
Rates of recent pain in this study were similar to population-based studies reporting that 67% of Australians aged 15 years and over  and 66% of Swedish adults  had experienced recent pain. These findings suggest that pain is a common, likely “normal”, human experience, even among healthy individuals. Notably, while the overall prevalence of bodily pain in our study was similar to population-based reports, moderate or severe pain was much lower; 16% of adult males and 13% of adult females reported moderate/severe pain, compared to population-based reports of 27% and 31%, respectively . It might be that individuals with moderate/severe pain were less likely to volunteer or be recruited into our study due to perceptions of health status or due to physical or psychological disability, given that higher pain intensity is linked with greater disability . In our study adults with chronic pain were older, in keeping with previous research , , although results from earlier studies are conflicting , . Nonetheless, this finding suggests a greater acceptance of pain as a “normal” phenomenon, particularly among older adults.
Despite selecting healthy individuals, adults with recent/chronic pain in our study were more likely to be overweight/obese and had lower physical performance, although effect sizes were small. While an association between pain and overweight/obesity has been established , , , , , , particularly among older adults in whom abdominal obesity almost doubles the likelihood of chronic pain , the direction and nature of this complex relationship remains an area for further investigation , . One hypothesis is that adipocytokines could provide a metabolic link between obesity and inflammatory conditions, as demonstrated in osteoarthritis  and low back pain . Nevertheless, an important clinical implication arising from these observations is the potential for treatments targeting both obesity and pain. For example, there is promising evidence for lifestyle interventions resulting in weight loss, improved function and decreased pain among adults with knee pain , , , likely attributable to reductions in both mechanical load and systemic inflammation , .
Our finding that adults with recent/chronic pain reported lower mental health is in keeping with the literature; lower mental health has been associated with spinal pain and is prognostic of worse outcomes , , . This is consistent with the growing focus on the multi-dimensionality of pain , . Efforts have been made to integrate psychosocial factors in back pain assessment , however our data suggest that screening and addressing broader health risks is also necessary, a practice promoted through the “Making every contact count” initiative of the UK National Health Service . Further, although longitudinal studies regarding the prognostic value of mental health in otherwise healthy people are needed, these findings could indicate a pre-clinical state and early intervention strategies to address these modifiable factors should be evaluated.
This study has several limitations. First, as the questions used to measure recent and chronic pain were generic, we cannot ascertain the body site affected or the underlying cause of pain. Second, we did not employ random sampling techniques. Although the highly-structured convenience sampling strategy targeted individuals from a wide range of backgrounds reflective of the ethnic diversity of the Australian population, our participants were from more socio-economically advantaged areas, and this may influence results. Third, as we measured generalised and not pain-specific self-efficacy, further studies investigating pain self-efficacy among healthy individuals are indicated.
Ultimately, understanding the characteristics of adults who report pain yet consider themselves healthy and maintain normal (or sufficient) functioning can help identify factors that protect against pain-related disability. Importantly, in our study levels of self-efficacy were similar between healthy adults with and without chronic pain. Although we measured general and not pain-specific self-efficacy, other studies have shown that pain self-efficacy is an important determinant of disability  and also mediates the relationship between chronic pain and disability , . High self-efficacy could help in maintaining good health and function despite pain, an observation supported by previous studies finding higher self-efficacy predicts better health outcomes among individuals with low back pain , . We also found that levels of physical activity were similar between adults with and without recent/chronic pain. While evidence for the link between physical activity and pain is mixed , it is possible that high physical activity could contribute to the preservation of good health in the presence of pain, although our cross-sectional study design precludes drawing inferences about cause and effect. Other factors such as resilience also likely contribute to protecting against pain-related disability and warrant further investigation .
Mild pain is common among healthy individuals. Adults who consider themselves healthy but experience pain (recent/chronic) display slightly lower mental health and physical performance, although these differences are unlikely clinically significant.
The findings of this study emphasise the importance of assessing pain-related disability in addition to prevalence when considering the disease burden of pain. Early assessment of broader health and lifestyle risk factors in clinical practice is emphasised. Avenues for future research include examination of whether lower mental health and physical performance represent risk factors for future pain and whether physical activity levels, sleep and self-efficacy are protective against chronic pain-related disability.
The authors wish to thank Ray Patton and John Eisenhuth for technical support, and all volunteers who contributed to the 1,000 Norms Project.
Vos T, Barber RM, Bell B, Bertozzi-Villa A, Biryukov S, Bolliger I, Charlson F, Davis A, Degenhardt L, Dicker D. Global, regional, and national incidence, prevalence, years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet 2015;386:743–800. PubMedCrossrefGoogle Scholar
Langley P, Müller-Schwefe G, Nicolaou A, Liedgens H, Pergolizzi J, Varrassi G. The societal impact of pain in the European Union: health-related quality of life and healthcare resource utilization. J Med Econ 2010;13:571–81. CrossrefPubMedGoogle Scholar
Australian Bureau of Statistics. Facts at your fingertips: health. Data from the National Health Survey, 2007–2008. ABS cat. no. 4841.0, 2011. Google Scholar
Thomas E, Peat G, Harris L, Wilkie R, Croft PR. The prevalence of pain and pain interference in a general population of older adults: cross-sectional findings from the North Staffordshire Osteoarthritis Project (NorStOP). Pain 2004;110:361–8. CrossrefGoogle Scholar
International Pain Summit of the International Association for the Study of Pain. Declaration of Montreal: declaration that access to pain management is a fundamental human right. J Pain Palliat Care Pharmacother 2011;25:29–31. PubMedGoogle Scholar
Fayaz A, Croft P, Langford R, Donaldson L, Jones G. Prevalence of chronic pain in the UK: a systematic review and meta-analysis of population studies. BMJ Open 2016;6:e010364. CrossrefPubMedGoogle Scholar
Pincus T, Burton AK, Vogel S, Field AP. A systematic review of psychological factors as predictors of chronicity/disability in prospective cohorts of low back pain. Spine (Phila Pa 1976) 2002;27:e109–20. CrossrefPubMedGoogle Scholar
Lumley MA, Cohen JL, Borszcz GS, Cano A, Radcliffe AM, Porter LS, Schubiner H, Keefe FJ. Pain and emotion: a biopsychosocial review of recent research. J Clin Psychol 2011;67:942–68. PubMedCrossrefGoogle Scholar
Jones EA, McBeth J, Nicholl B, Morriss RK, Dickens C, Jones GT, Macfarlane GJ. What characterizes persons who do not report musculoskeletal pain? Results from a 4-year population-based longitudinal study (the Epifund study). J Rheumatol 2009;36:1071–7. PubMedCrossrefGoogle Scholar
McKay MJ, Baldwin JN, Ferreira P, Simic M, Vanicek N, Hiller CE, Nightingale EJ, Moloney NA, Quinlan KG, Pourkazemi F, Sman AD, Nicholson LL, Mousavi SJ, Rose K, Raymond J, Mackey MG, Chard A, Hübscher M, Wegener C, Fong Yan A, et al. 1000 Norms Project: protocol of a cross-sectional study cataloging human variation. Physiotherapy 2016;102:50–6. CrossrefPubMedGoogle Scholar
Australian Bureau of Statistics. Population by age and sex, regions of Australia, 2012. ABS cat. no. 3235.0. Canberra, Australia, 2012. Google Scholar
Australian Bureau of Statistics. Australian Standard Classification of Cultural and Ethnic Groups (ASCCEG), 2011. ABS cat. no. 1249.0. Canberra, Australia, 2011. Google Scholar
Trewin D. Socio-economic indexes for areas (SEIFA). Canberra, Australia: Australian Bureau of Statistics, 2001. Google Scholar
Merskey H, Bogduk N. Classification of chronic pain, IASP Task Force on Taxonomy. Seattle, WA: International Association for the Study of Pain Press, 1994. Google Scholar
Richardson J, Khan M, Iezzi A, Sinha K, Mihalopoulos C, Herrman H, Hawthorne G, Schweitzer I. The AQoL-8D (PsyQoL) MAU Instrument: overview September 2009. Melbourne, Australia: Centre for Health Economics, Faculty of Business and Economics, Monash University, 2009. Google Scholar
Cappelleri JC, Bushmakin AG, McDermott AM, Sadosky AB, Petrie CD, Martin S. Psychometric properties of a single-item scale to assess sleep quality among individuals with fibromyalgia. Health Qual Life Outcomes 2009;7:54–60. CrossrefPubMedGoogle Scholar
Craig CL, Marshall AL, Sjostrom M, Bauman AE, Booth ML, Ainsworth BE, Pratt M, Ekelund U, Yngve A, Sallis JF, Oja P. International Physical Activity Questionnaire: 12-country reliability and validity. Med Sci Sports Exerc 2003;35:1381–95. CrossrefPubMedGoogle Scholar
Hurtig-Wennlöf A, Hagströmer M, Olsson LA. The International Physical Activity Questionnaire modified for the elderly: aspects of validity and feasibility. Public Health Nutr 2010;13:1847–54. CrossrefPubMedGoogle Scholar
Australian Bureau of Statistics. National Health Survey: First Results, 2014-15. ABS cat. no. 4364.0.55.001. Canberra, Australia, 2015. Google Scholar
ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002;166:111–7. PubMedGoogle Scholar
Zaino CA, Marchese VG, Westcott SL. Timed up and down stairs test: preliminary reliability and validity of a new measure of functional mobility. Pediatr Phys Ther 2004;16:90–8. CrossrefPubMedGoogle Scholar
Hof AL. Scaling gait data to body size. Gait Posture 1996;3:222–3. Google Scholar
Harris PA, Taylor R, Thielke R, Payne J, Gonzalez N, Conde JG. Research electronic data capture (REDCap): a metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inform 2009;42: 377–81. CrossrefPubMedGoogle Scholar
Australian Bureau of Statistics. Reflecting a Nation: Stories from the 2011 Census, 2012–2013. ABS cat. no. 2071.0. Canberra, Australia, 2013. Google Scholar
Australian Bureau of Statistics. Estimates and projections, Aboriginal and Torres Strait Islander Australians, 2001 to 2026. ABS cat. no. 3238.0. Canberra, Australia, 2015. Google Scholar
Australian Bureau of Statistics. Migration, Australia, 2013–2014. ABS cat. no. 3412.0. Canberra, Australia, 2014. Google Scholar
Denison E, Åsenlöf P, Lindberg P. Self-efficacy, fear avoidance, and pain intensity as predictors of disability in subacute and chronic musculoskeletal pain patients in primary health care. Pain 2004;111:245–52. CrossrefPubMedGoogle Scholar
Buskila D, Abramov G, Biton A, Neumann L. The prevalence of pain complaints in a general population in Israel and its implications for utilization of health services. J Rheumatol 2000;27:1521–5. Google Scholar
Felson DT, Zhang Y, Anthony JM, Naimark A, Anderson JJ. Weight loss reduces the risk for symptomatic knee osteoarthritis in women: the Framingham Study. Ann Intern Med 1992;116:535–9. PubMedCrossrefGoogle Scholar
Hitt HC, McMillen RC, Thornton-Neaves T, Koch K, Cosby AG. Comorbidity of obesity and pain in a general population: results from the Southern Pain Prevalence Study. J Pain 2007;8:430–6. CrossrefGoogle Scholar
Foy CG, Lewis CE, Hairston KG, Miller GD, Lang W, Jakicic JM, Rejeski WJ, Ribisl PM, Walkup MP, Wagenknecht LE. Intensive lifestyle intervention improves physical function among obese adults with knee pain: findings from the Look AHEAD trial. Obesity 2011;19:83–93. CrossrefGoogle Scholar
Fransen M, McConnell S, Harmer AR, Van der Esch M, Simic M, Bennell KL. Exercise for osteoarthritis of the knee. Cochrane Database Syst Rev 2015;1. DOI: 10.1002/14651858.CD004376.pub3. Google Scholar
Miller GD, Nicklas BJ, Davis C, Loeser RF, Lenchik L, Messier SP. Intensive weight loss program improves physical function in older obese adults with knee osteoarthritis. Obesity 2006;14:1219–30. CrossrefGoogle Scholar
Messier SP, Gutekunst DJ, Davis C, DeVita P. Weight loss reduces knee-joint loads in overweight and obese older adults with knee osteoarthritis. Arthritis Rheum 2005;52:2026–32. PubMedCrossrefGoogle Scholar
Carroll LJ, Holm LW, Hogg-Johnson S, Côtè P, Cassidy JD, Haldeman S, Nordin M, Hurwitz EL, Carragee EJ, van der Velde G, Peloso PM, Guzman J. Course and prognostic factors for neck pain in Whiplash-Associated Disorders (WAD): results of the Bone and Joint Decade 2000–2010 task force on neck pain and its associated disorders. J Manipulative Physiol Ther 2009;32(2, Supplement):S97–107. PubMedCrossrefGoogle Scholar
Hendriks EJ, Scholten-Peeters GG, van der Windt DA, Neeleman-van der Steen CW, Oostendorp RA, Verhagen AP. Prognostic factors for poor recovery in acute whiplash patients. Pain 2005;114:408–16. PubMedCrossrefGoogle Scholar
Rabey M, Beales D, Slater H, O’Sullivan P. Multidimensional pain profiles in four cases of chronic non-specific axial low back pain: an examination of the limitations of contemporary classification systems. Man Ther 2015;20:138–47. PubMedCrossrefGoogle Scholar
Hill JC, Dunn KM, Main CJ, Hay EM. Subgrouping low back pain: a comparison of the STarT Back Tool with the Örebro musculoskeletal pain screening questionnaire. Eur J Pain 2010;14:83–9. CrossrefPubMedGoogle Scholar
Lawrence W, Black C, Tinati T, Cradock S, Begum R, Jarman M, Pease A, Margetts B, Davies J, Inskip H. ‘Making every contact count’: evaluation of the impact of an intervention to train health and social care practitioners in skills to support health behaviour change. J Health Psychol 2016;21:138–51. CrossrefPubMedGoogle Scholar
Lee H, Hübscher M, Moseley GL, Kamper SJ, Traeger AC, Mansell G, McAuley JH. How does pain lead to disability? A systematic review and meta-analysis of mediation studies in people with back and neck pain. Pain 2015;156:988–97. PubMedGoogle Scholar
Arnstein P, Caudill M, Mandle CL, Norris A, Beasley R. Self efficacy as a mediator of the relationship between pain intensity, disability and depression in chronic pain patients. Pain 1999;80:483–91. CrossrefPubMedGoogle Scholar
Woby SR, Roach NK, Urmston M, Watson PJ. Outcome following a physiotherapist-led intervention for chronic low back pain: the important role of cognitive processes. Physiotherapy 2008;94:115–24. CrossrefGoogle Scholar
Sitthipornvorakul E, Janwantanakul P, Purepong N, Pensri P, van der Beek AJ. The association between physical activity and neck and low back pain: a systematic review. Eur Spine J 2011;20:677–89. CrossrefPubMedGoogle Scholar
Authors represent the 1,000 Norms Project Consortium. The members of the Consortium are as follows: University of Sydney, Sydney: Jennifer Baldwin, Marnee McKay, Angus Chard, Paulo Ferreira, Alycia Fong Yan, Claire Hiller, Fiona Lee (nee Zheng), Martin Mackey, Seyed Mousavi, Leslie Nicholson, Elizabeth Nightingale, Fereshteh Pourkazemi, Jacqueline Raymond, Kristy Rose, Milena Simic, Amy Sman, Caleb Wegener, Kathryn Refshauge and Joshua Burns; Macquarie University, Sydney: Niamh Moloney; Murdoch Childrens Research Institute, Melbourne: Kathryn North; Neuroscience Research Australia, Sydney: Markus Hübscher; University of Hull, Hull: Natalie Vanicek; University of New South Wales, Sydney: Kate Quinlan.
About the article
Published Online: 2018-02-02
Research funding: This study was supported by grants from the National Health and Medical Research Council of Australia Centre for Research Excellence in Neuromuscular Disorders (NHMRC #1031893) and Australian Podiatry Education and Research Foundation, as well as scholarship funding from the Australian Postgraduate Award from the Commonwealth Government of Australia.
Conflict of interest: There are no conflicts of interest for any of the listed authors.
Informed consent: Informed, written consent was given by all participants aged 18 years and over, or by the parent/guardian of participants aged under 18 years.
Ethical approval: The institutional Ethics Committee approved the study (HREC 2013/640).
Citation Information: Scandinavian Journal of Pain, 20170156, ISSN (Online) 1877-8879, ISSN (Print) 1877-8860, DOI: https://doi.org/10.1515/sjpain-2017-0156.