Skip Navigation


Age and Ageing Advance Access originally published online on January 27, 2007
Age and Ageing 2007 36(2):145-151; doi:10.1093/ageing/afl167
This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
36/2/145    most recent
afl167v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (6)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Peel, N. M.
Right arrow Articles by Hendrikz, J. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Peel, N. M.
Right arrow Articles by Hendrikz, J. K.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Copyright © The Author 2007. Published by Oxford University Press on behalf of the British Geriatrics Society.

Psychosocial factors associated with fall-related hip fractures

Nancye M. Peel1,2,*, Roderick J. McClure3 and Joan K. Hendrikz2

1 University of Queensland, Australasian Centre on Ageing, St Lucia, Queensland, Australia
2 University of Queensland, Centre of National Research on Disability and Rehabilitation Medicine, Herston, Queensland, Australia
3 Griffith University, School of Medicine, Meadowbrook, Queensland, Australia

Address correspondence to: Nancye M. Peel. Email: n.peel{at}uq.edu.au


   Abstract
Top
 Abstract
Introduction
 Methods
 Results
 Discussion
 Policy Implications
 Conclusion
 Key points
 References
 
Background: fall-related injuries in older people are a major public health concern. This study examined the relationship between psychosocial determinants of healthy ageing and risk of fall-related hip fracture in community-dwelling older people. The purpose was to contribute evidence for promotion of healthy ageing strategies in population-based interventions for fall injury prevention.

Methods: a case-control study was conducted with 387 participants, with at least two controls recruited per case. Cases of fall-related hip fracture in community-dwelling people aged 65 and older were recruited from hospital admissions in Brisbane, Australia, in 2003–2004. Community-based controls, matched by age, sex and postcode, were recruited via electoral roll sampling. A questionnaire assessing psychosocial factors, identified as determinants of healthy ageing, was administered at face-to-face interviews.

Results: psychosocial factors having a significant independent protective effect on hip fracture risk included being currently married [OR: 0.44 (0.22 to 0.88)], living in present residence for 5 years or more [OR: 0.43 (0.22 to 0.84)], having private health insurance [OR: 0.49 (0.27 to 0.90)], using proactive coping strategies [OR: 0.52 (0.29 to 0.92)], having a higher level of life satisfaction [OR: 0.47 (0.27 to 0.81)], and engagement in social activities in older age [OR: 0.30 (0.17 to 0.54)].

Conclusion: this study suggests that psychosocial determinants of healthy ageing are protective in fall-related hip fracture injury in older people. Reduction in the public health burden caused by this injury may then be achieved by implementing healthy ageing strategies involving community-based approaches to enhance the psychosocial environments of older people.

Keywords: hip fractures, case-control study, psychosocial factors, aged population, falls prevention, elderly


   Introduction
Top
 Abstract
 Introduction
Methods
 Results
 Discussion
 Policy Implications
 Conclusion
 Key points
 References
 
Injuries resulting from falls in older people are a major public health concern, representing a main cause of disability and death in this population [1]. Current fall prevention strategies are based on a rehabilitation intervention model to identify and treat those at high risk [2]. This has directed attention to the role of modifiable behavioural factors aimed at risk reduction in individuals. A neglected area of research is the contribution of psychosocial factors to the management of fall-related injury risk.

Several psychosocial factors that are potential risk factors have been suggested [3], based on their general association with other diseases or disabilities, especially those relating to falling. Suggested factors include marital status, living arrangements, stress and coping, life satisfaction, emotional status, cognition and social connectedness [3]. Large prospective studies investigating hip fracture as an outcome [4–8] have included some of these measures, but the strength of their association with fall-related injury is often significant only in univariate analysis.

Psychosocial factors are increasingly acknowledged as important determinants of healthy ageing [9]; however, their role in the causation of adverse health outcomes related to ageing, such as fall-related hip fractures, remains unclear. The present study aimed to examine the relationship between psychosocial determinants of healthy ageing and risk of fall-related hip fracture in community-dwelling older people. The purpose was to contribute evidence for promotion of healthy ageing strategies in population-based interventions for fall injury prevention.


   Methods
Top
 Abstract
 Introduction
 Methods
Results
 Discussion
 Policy Implications
 Conclusion
 Key points
 References
 
Study design and participants
A case–control study was conducted in Brisbane, capital of Queensland on the eastern coast of Australia. Eligible cases were aged 65 years or over and admitted to one of six metropolitan hospitals for treatment of a fall-related hip fracture. For each case, at least two controls were randomly selected from the electoral roll, after matching on sex, age (within a 5 year age range) and postcode. Residents of high care institutions were ineligible.

Data collection
On the basis of literature review of the measurement and determinants of healthy ageing [10], psychosocial determinants that might plausibly be related to hip fracture were included in a questionnaire administered at face-to-face interviews. A proxy was sought when the score on a comprehension test of cognitive capacity, administered at interview, was below the threshold of seven out of ten correct answers for questions assessing orientation to person, place and time.

Study factors
The psychosocial factors were divided into three domains—community support systems, psychological well-being and engagement with life. Where variables pertained to different life stages, these were defined as older age (65 and over), middle age (40 to 64), and young adulthood (15 to 39).

Community support measures included marital status, household composition, residential environment (general community, retirement villages or hostel care), length of residence (years in dwelling) and community integration [11]. Social support was an additive score from questions about size of friendship network, frequency of contact, feelings of loneliness, having a confidant and presence of help in times of need [12]. Carer status (whether a carer or in receipt of care) and private health insurance (PHI) cover were also ascertained.

Psychological well-being measures included self-rated general health, emotional health (frequency of feelings of sadness, nervousness, tiredness and worthlessness [13]) and exposure to stress (in areas of health, family relationships, and daily living activities). Proactive or avoidance coping mechanisms for handling stress were coded from a ‘Ways of Coping Checklist’ [14]. Other measures included recent adverse life events (from a list relevant to older people), morale (derived from seven questions on attitudes towards own ageing and self-efficacy [15]) and importance of religion coded as a single item question (‘Do you pray or live by the principles of religion?’). A single item question about life satisfaction was measured for three life periods (older age, middle age and as a young adult).

Life engagement measures included independent functioning in instrumental activities of daily living (IADL) such as managing the telephone, transport, shopping, meal preparation, home maintenance, medications and money. Driving status (currently driving, being an ex-driver, or never having driven) was also included as a measure of independent functioning. Involvement in a number of activities grouped into productive and social activities [16] was recorded for two periods (older age, middle age).

Other data included demographics (age, sex, education, financial status and country of birth) and self-reported health measures (co-morbidities, sensori-motor impairments, medications, physical limitations and fall history). The list of co-morbidities included a diagnosis of heart problems, cancer, osteoporosis, diabetes, stroke, Parkinson's Disease, respiratory disease, depression or other major illness. Sensori-motor impairments recorded were having a hip replacement, eyesight problems, hearing loss, incontinence, arthritis, difficulty sleeping, dizziness/loss of balance, or needing walking aids. Lifestyle factors included smoking history, alcohol consumption, diet, physical activity and other health protective behaviours. The association of lifestyle behavioural factors with the risk of fall-related hip fractures has previously been reported [17].

Analysis
Stata 9.0 (StataCorp College Station, TX, 2005) was used in conditional logistic regression analysis to produce Odds Ratios (ORs) with 95% confidence intervals (CIs) for the effect of exposure variables on the outcome of hip fracture. Multivariate models were developed for psychosocial factors by adding, in step-wise progression, factors significant in univariate analysis at the probability (P) value of less than 0.05.

Two-way interactions between the psychosocial factors, age and sex were added to the main effects model if significant at the P<0.1 level. Also added to the model were potential confounders, chosen from health status factors shown to be significant predictors of outcome in univariate analysis and on the basis, from understanding of the literature, that they could plausibly be associated with the factors of interest. Criteria for retention of confounders in the model were that they were significant independent predictors in the multivariate model and substantially changed the ORs of the psychosocial factors by more than 10%. At each stage in the modelling process, models were compared using best fit statistics to select the most parsimonious model [18].


   Results
Top
 Abstract
 Introduction
 Methods
 Results
Discussion
 Policy Implications
 Conclusion
 Key points
 References
 
In total, 126 cases and 261 controls completed an interviewer-administered questionnaire. The overall participation rate of eligible subjects was 85% (93% for cases and 81% for controls). Chi-square tests showed there were no significant differences between participants and non-participants on sex or age group distribution. Proxies assisted with 25 (6.5%) interviews, with no significant differences between cases and controls on proxy use, cognitive assessment score or on demographic variables (education, financial status, ethnicity). The distribution of demographic characteristics in the study population is shown in Table 1.


View this table:
[in this window]
[in a new window]

  		Table 1. Demographic characteristics of the study population

 
The psychosocial factors significant in univariate analysis are summarised in Table 2.


View this table:
[in this window]
[in a new window]

  		Table 2. Psychosocial factors significant in univariate analysis

 
The final psychosocial model, adjusted for confounding effects of health status measures, is shown in Table 3. The pseudo R-squared value of 27% indicated the percentage predictability of the model.


View this table:
[in this window]
[in a new window]

  		Table 3. Psychosocial factors significant in multivariate analysis

 
Health status measures that remained significant independent predictors of hip fracture included having a history of osteoporosis, respiratory disease, and hearing problems. Inclusion of these factors improved the predictive capability of the model (pseudo R-squared of 33%). However, none of the health status factors entered in the model changed the ORs of the psychosocial factors by more than 10%, so that no adjustment of the main effects model was necessary. While interactions produced some effect modification for different levels of the psychosocial factors, their inclusion did not improve the fit statistics and they were not included in the final model for the sake of parsimony [18].

In the final psychosocial model, 12 cases (9.5%) and 14 controls (5.4%) had missing data on at least one of the six factors. Examination of available data for these records suggested that subjects fitted the outcome profiles to which they were assigned and would have, if included, reinforced the results obtained.


   Discussion
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
Policy Implications
 Conclusion
 Key points
 References
 
This study suggests that psychosocial determinants of healthy ageing are protective of the special case adverse outcome of fall-related hip fracture injury in older people. The factors that significantly protect against fall-related hip fractures are currently being married, living in present residence for five years or more, having PHI, using proactive coping strategies in response to stress, having a higher level of life satisfaction and engagement in social activities in older age. The findings are discussed for each of the psychosocial factors and compared with supporting evidence where available.

In univariate analysis, being currently married was significantly protective of hip fracture, as was living with others (Table 2). When further sub-categorised (data not shown), those who were living with their spouse were significantly protected, rather than those living with someone other than their spouse. Being currently married compared with not currently married (i.e. being widowed, divorced or unmarried) remained significantly protective in multivariate models. Previous studies have reported that being unmarried and/or living alone are independent risk factors for hip fracture [7, 19], particularly for women [7]. Evidence also shows that current marital status, rather than marital history, is a determinant of hip fracture risk, with widowed, divorced and unmarried women having a higher risk of hip fracture than those married or cohabitating [20]. A possible explanation for this relationship is that marriage has beneficial effects on health behaviours [21]. Living alone represents an exposure to poorer diet, greater intake of medication, lower levels of physical activity, and a diminished social network [19] as well as increased frailty [22], all of which are associated with increased risk of hip fracture [22].

Living in the present dwelling for five years or more was significantly protective in multivariate models of psychosocial factors. On measures of community integration, there were significant differences in hip fracture risk between cases and controls in univariate analysis (Table 2), but these differences did not persist in multivariate models. While ‘ageing in place’ is increasingly being endorsed by governments, not only in Australia, but in Europe, North America and the United Kingdom, there has been little previous research linking length of time in residence and community integration to adverse health outcomes such as hip fractures. An explanation for the findings may be that those who have lived longer at their present address have a better sense of belonging to their neighbourhood, which in turn is associated with better physical and mental health [23]. Familiarity with the environment may also reduce the risk of falling since hip fracture risk has been linked with a wide range of environmental hazards [24].

Consistent with previous findings [4, 5], having a high level of social support was significant in univariate analysis, while PHI remained significantly protective in multivariate models. Private health cover could conceivably influence access to health care, leading to better health outcomes and protection against hip fracture [5].

Indicators of psychological well-being significantly related to hip fracture risk in univariate analysis in this study included emotional health, coping strategies, exposure to recent adverse life events, morale, life satisfaction and religious belief (Table 2). Factors that remained independently protective of hip fracture risk, after adjusting for other health status variables, were use of proactive coping strategies and being very satisfied with life in older age (Table 3). These findings are supported by the results of other studies which have shown that psychological distress, especially depression, is associated with fracture risk [6], as is exposure to recent adverse life events [25]. Resilience, as measured by stress coping ability, is thought to have a buffering role in reducing adverse consequences of stressors and thus contributes to psychological well-being [26]. Low self-efficacy has been found to be a risk for falls because of associated fear of falling and consequent activity restriction [27]. Life satisfaction, another measure of psychological well-being, has also been associated with hip fracture risk [6]. Spiritual beliefs have been linked with lower levels of depression and better ambulatory status in hip fracture patients [28].

Measures indicative of active engagement with life were found to be significantly protective of hip fracture risk in univariate analysis. These factors included social functioning (independence in IADL), being a current driver, and participation in productive and social activities in middle and older age (Table 2). In multivariate models, social participation in older age remained significantly protective of hip fracture risk (Table 3). While curtailment of social functioning following hip fracture is well documented, there is little research on pre-fracture activities. An explanation of the findings of this study may be that meaningful social roles may promote better health outcomes through a number of psychosocial pathways [16].

While cognitive incapacity is a known risk factor for hip fracture [4], mental capacity scores were not significantly different between cases and controls in this study. However, selection criteria specifically screened for and excluded those with moderate to severe cognitive impairment, which limits generalisability of the study results.

The strengths of the present study are the rigour of the methodology, with population-based case and control groups, a high response rate, low level of missing data and adequate control for confounding. There are plausible explanations as to mechanisms whereby psychosocial factors maintain health, and are thus protective of an adverse health outcome. Limitations of the study are those associated with case–control designs, including recall bias and reliance on self-reported retrospective data. While many of the psychosocial traits such as morale and coping skills are thought to be stable over time [29], a limitation of cross-sectional data still remains that causal relationships are difficult to establish and perceptions of events may well be influenced by outcome status. The results would need to be corroborated in prospective studies to draw causal inferences. A further limitation of the study is that, in investigating a large number of factors, relationships may be statistically significant by chance alone. For this reason, variable selection was based on a priori hypotheses and model building process guidelines followed [18].


   Policy Implications
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 Policy Implications
Conclusion
 Key points
 References
 
The evidence suggests that a range of personal, social and environmental factors play a role in promoting healthy ageing and preventing fall-related hip fractures. The challenge is to develop effective strategies involving community-based approaches to enhance the psychosocial environments for older people. Opportunities for healthy and productive ageing can be increased substantially by facilitating participation in both the paid and volunteer workforce. Community engagement programmes build social capital and reduce social isolation. Creating ‘age-friendly’ built environments, and access to assistive technology provides opportunities for independence, ‘ageing in place’ and healthy lifestyles through increased physical and social activity. Valuing the significant contributions made by older people to society and emphasising positive aspects of ageing through intergenerational programmes can assist in breaking down age stereotypes and ageist attitudes [30].


   Conclusion
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 Policy Implications
 Conclusion
Key points
 References
 
This study has shown an important association between psychosocial factors and hip fracture. To corroborate these results, further prospective studies on diseases and disabilities common in older age should include, and more accurately measure, these psychosocial factors. The results of this study suggest that, by optimising opportunities for improving and preserving health and physical, social and mental wellness, independence and quality of life—i.e. pursuing the goals of healthy ageing—reduction in the public health burden of fall-related hip fracture may be achieved.

Declaration of sources of funding
The research was supported by an RM Gibson Scientific Research Fund Grant from the Australian Association of Gerontology. The funders played no role in the design, conduct, analysis or interpretation of the data, nor writing of the manuscript.

Conflict of interest statement
There are no conflicts of interest to declare.

Ethical approval
Ethical approval for the study was obtained from the University and Hospital Health Ethics Committees. After receiving information about the project and an invitation to participate, all subjects (or their proxy health carers) gave written consent to participate.


   Key points
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 Policy Implications
 Conclusion
 Key points
References
 

  • There have been few previous studies examining the association between psychosocial factors and risk of fall-related hip fractures.
  • Psychosocial factors having a significant independent protective effect on hip fracture risk included being currently married, living in present residence for five years or more, having PHI, resilience in response to stress, having a higher level of life satisfaction and engagement in social activities in older age.
  • The study suggests that fall injury prevention among older people may be addressed by implementing healthy ageing strategies involving community-based approaches to enhance their psychosocial environments.


   References
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 Policy Implications
 Conclusion
 Key points
 References
 

  1. Kannus P, Sievanen H, Palvanen M, Jarvinen T, Parkkari J. (2005) Prevention of falls and consequent injuries in elderly people. Lancet 366 1885–93.[CrossRef][Web of Science][Medline]
  2. Gillespie L. (2004) Preventing falls in elderly people. BMJ 328 653–4.[Free Full Text]
  3. Mossey JM. (1985) Social and psychologic factors related to falls among the elderly. Clin Geriatr Med 1 541–53.[Medline]
  4. Taylor BC, Schreiner PJ, Stone KL, et al. (2004) Long-term prediction of incident hip fracture risk in elderly white women: study of osteoporotic fractures. J Am Geriatr Soc 52 1479–86.[CrossRef][Web of Science][Medline]
  5. Wilson RT, Chase GA, Chrischilles EA, Wallace RB. (2006) Hip fracture risk among community-dwelling elderly people in the United States: a prospective study of physical, cognitive, and socioeconomic indicators. Am J Public Health 96 1210–8.[Abstract/Free Full Text]
  6. Forsen L, Meyer HE, Sogaard AJ, Naess S, Schei B, Edna TH. (1999) Mental distress and risk of hip fracture. Do broken hearts lead to broken bones? J Epidemiol Community Health 53 343–7.[Abstract]
  7. Espino DV, Palmer RF, Miles TP, et al. (2000) Prevalence, incidence, and risk factors associated with hip fractures in community-dwelling older Mexican Americans: results of the Hispanic EPESE study. J Am Geriatr Soc 48 1252–60.[Web of Science][Medline]
  8. Wolinsky FD and Fitzgerald JF. (1994) The risk of hip fracture among noninstitutionalized older adults. J Gerontol 49 S165–75.[Abstract/Free Full Text]
  9. Depp CA and Jeste DV. (2006) Definitions and predictors of successful aging: a comprehensive review of larger quantitative studies. Am J Geriatr Psychiatry 14 6–20.[CrossRef][Web of Science][Medline]
  10. Peel NM, Bartlett HP, McClure RJ. (2004) Healthy ageing: how is it defined and measured? Australas J Ageing 23 115–9.
  11. McColl MA, Davies D, Carlson P, Johnston J, Minnes P. (2001) The community integration measure: development and preliminary validation. Arch Phys Med Rehabil 82 429–34.[CrossRef][Web of Science][Medline]
  12. Fillenbaum G, Gallo J, Fulmer T, Paveza G, Reichel W. (2000) Handbook of Geriatric Assessment 2nd edition Rockville, MD Aspen Publishers.
  13. Kessler RC, Andrews G, Colpe LJ, et al. (2002) Short screening scales to monitor population prevalences and trends in non-specific psychological distress. Psychol Med 32 959–76.[CrossRef][Web of Science][Medline]
  14. Vitaliano PP, Russo J, Carr J, Maluro R, Becker J. (1985) The ways of coping checklist: revision and psychometric properties. Multivariate Behav Res 20 3–26.
  15. Pearlin LI and Schooler C. (1978) The structure of coping. J Health Soc Behav 19 2–21.[Medline]
  16. Glass TA, de Leon CM, Marottoli RA, Berkman LF. (1999) Population based study of social and productive activities as predictors of survival among elderly Americans. BMJ 319 478–83.[Abstract/Free Full Text]
  17. Peel NM, McClure RJ, Hendrikz JK. (2006) Health-protective behaviours and risk of fall-related hip fractures: a population-based case-control study. Age Ageing 35 491–7.[Abstract/Free Full Text]
  18. Hosmer DW and Lemeshow S. (2000) Applied Logistic Regression 2nd edition New York Wiley.
  19. Hokby A, Reimers A, Laflamme L. (2003) Hip fractures among older people: do marital status and type of residence matter? Public Health 117 196–201.[CrossRef][Web of Science][Medline]
  20. Farahmand BY, Persson PG, Michaelsson K, Baron JA, Parker MG, Ljunghall S. (2000) Socioeconomic status, marital status and hip fracture risk: a population-based case-control study. Osteoporos Int 11 803–8.[CrossRef][Web of Science][Medline]
  21. Schone BS and Weinick RM. (1998) Health-related behaviors and the benefits of marriage for elderly persons. Gerontologist 38 618–27.[Abstract]
  22. Woods NF, LaCroix AZ, Gray SL, et al. (2005) Frailty: emergence and consequences in women aged 65 and older in the Women's Health Initiative Observational Study. J Am Geriatr Soc 53 1321–30.[CrossRef][Web of Science][Medline]
  23. Young AF, Russell A, Powers JR. (2004) The sense of belonging to a neighbourhood: can it be measured and is it related to health and well being in older women? Soc Sci Med 59 2627–37.[CrossRef][Web of Science][Medline]
  24. Clemson L, Cumming RG, Roland M. (1996) Case-control study of hazards in the home and risk of falls and hip fractures. Age Ageing 25 97–101.[Abstract/Free Full Text]
  25. Peterson MG, Allegrante JP, Augurt A, Robbins L, MacKenzie CR, Cornell CN. (2000) Major life events as antecedents to hip fracture. J Trauma 48 1096–100.[Web of Science][Medline]
  26. Kahana E, Kahana B, Kercher K. (2003) Emerging lifestyles and proactive options for successful ageing. Ageing Int 28 155–80.
  27. Fletcher PC and Hirdes JP. (2004) Restriction in activity associated with fear of falling among community-based seniors using home care services. Age Ageing 33 273–9.[Abstract/Free Full Text]
  28. Pressman P, Lyons JS, Larson DB, Strain JJ. (1990) Religious belief, depression, and ambulation status in elderly women with broken hips. Am J Psychiatry 147 758–60.[Abstract/Free Full Text]
  29. Costa PT, Metter EJ, McCrae RR. (1994) Personality stability and its contribution to successful aging. J Geriatr Psychiatry 27 41–59.
  30. Bartlett HP and Peel NM. (2005) Healthy ageing in the community. In Andrews GJ and Phillips DR (Eds.). Ageing and Place: Perspectives, Policy, PracticeLondon, New York Routledge pp. 98–109.
Received 11 July 2006; accepted in revised form 6 November 2006.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?



This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
36/2/145    most recent
afl167v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (6)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Peel, N. M.
Right arrow Articles by Hendrikz, J. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Peel, N. M.
Right arrow Articles by Hendrikz, J. K.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?