By Moira Stewart, Martin Fortin, Helena Britt, Christopher Harrison, and Heather Maddocks
A recent study published in Family Practice “Comparisons of multi-morbidity in family practice – issues and biases” [1] compared the methods and results of three separate prevalence studies of multi-morbidity from; i) the Saguenay region of Quebec [2]; ii) a sub-study of the Bettering Evaluation and Care of Health (BEACH) program in Australia [3,4]; and iii) the Deliver Primary Health Care Information (DELPHI) project in South-western Ontario [5,6].
A re-estimate of the prevalence rates using identical age-sex groups found multi-morbidity prevalence to vary by as much as 61%, where reported prevalence was 95% among females aged 45–64 in the Saguenay study, 46% in the BEACH sub-study and 34% in the DELPHI study.
Several aspects of the methods and study designs were identified as differing among the studies, including the sampling of frequent attenders, sampling period, source of data, and both the definition and count of chronic conditions.
The paper offers a guide for authors reporting the methods used in multi-morbidity prevalence research, recommending detailed descriptions of the type of sampling, completeness and accuracy of the source of data, and the definition of chronic conditions.
Further comparisons among multi-morbidity data using agreed upon standards for the definition of chronic conditions and the way to count multi-morbidity are recommended to assess the impact of these methodological variations.
References:
1 Stewart M, Fortin M, Britt H, Harrison C, Maddocks H. Comparisons of multi-morbidity in family practice – issues and biases. Family Practice. May 2013. doi: 10.1093/fampra/cmt012.
2 Fortin M, Bravo G, Hudon C, Vanasse A, Lapointe L. Prevalence of multimorbidity among adults seen in family practice. Ann Fam Med 2005; 3: 223–8.
3 Britt HC, Harrison CM, Miller GC, Knox SA. Prevalence and patterns of multimorbidity in Australia. Med J Aust 2008; 189: 72–7.
4 Knox SA, Harrison CM, Britt HC, Henderson JV. Estimating prevalence of common chronic morbidities in Australia. Med J Aust 2008; 189: 66–70.
5 Stewart M, Thind A, Terry AL, et al. Multimorbidity in primary care: a study using electronic medical record (EMR) data. In: Thirty-Seventh Annual Meeting of North American Primary Care Research Group, Quebec, Canada, 14–18 November, 2009.
6 Stewart M, Thind A, Terry A, Chevendra V, Marshall JN. Implementing and maintaining a researchable database from electronic medical records—a perspective from an academic family medicine department. Healthc Policy 2009; 5: 26–39.