How do respondents of primary care surveys compare to typical users of primary care? A comparison of two surveys.

BACKGROUND: Primary care surveys are a key source of evaluative data; understanding how survey respondents compare to the intended population is important to understand results in context. The objective of this study was to examine the physician and patient representativeness of two primary care surveys (TRANSFORMATION and QUALICOPC) that each used different sampling and recruitment techniques. METHODS: We linked the physician and patient participants of the two surveys to health administrative databases. Patients were compared to other patients visiting the practice on the same day and other randomly selected dates using sociodemographic data, chronic disease diagnosis, and health system utilization. Physicians were compared to other physicians in the same practice, and other physicians in the intended geographic area using sociodemographic and practice characteristics. RESULTS: Physician respondents of the TRANSFORMATION survey included more males compared to their practice groups, but not to other physicians in the area. TRANSFORMATION physicians cared for a larger roster of patients than other physicians in the area. Patient respondents of the QUALICOPC survey did not have meaningful differences from other patients who visit the practice. Patient respondents of the TRANSFORMATION survey resided in more rural areas, had less chronic disease, and had lower use of health services than other patients visiting the practice. CONCLUSION: Differences in survey recruitment methods at the physician and patient level may help to explain some of the differences in representativeness. When conducting primary care surveys, investigators should consider diverse methods of ensuring representativeness to limit the potential for nonresponse bias.

Depression as a Risk Factor for Physical Illness and Multimorbidity in a Cohort with No Prior Comorbidity.

OBJECTIVE: This study examines whether depression is associated with the development of physical illness and multimorbidity, after controlling for socioeconomic, behavioral, and other potential confounders. METHODS: This is a retrospective cohort study in which adult respondents to three nationally representative population health surveys were linked to health administrative databases in Ontario, Canada, and followed for 10 years from survey index. Respondents with any of the study outcome conditions at baseline were excluded to create a final cohort of 29,838 participants. The main exposure of interest was depression, measured using the Composite International Diagnostic Interview-Short Form for Major Depression. We controlled for age, body mass index, marital status, immigrant status, annual household income, smoking, alcohol consumption, physical activity, health status, and having a regular doctor. The outcome measure was the development of physical illness over 10 years of follow-up, defined as 1 of 15 common chronic conditions using administrative data. RESULTS: Among the 29,838 participants (15,259 [51%] female), 8% of females and 4% of males had depression at baseline. In this cohort with no comorbidities at baseline, even in the fully adjusted model, depression increased the risk of developing a first physical illness for females (hazard ratio [HR] 1.16; 95% CI, 1.07 to 1.26) and males (HR 1.20; 95% CI, 1.07 to 1.36) and increased the risk of developing a second physical illness for females (HR 1.16; 95% CI, 1.02 to 1.33) over 10 years of follow-up. CONCLUSIONS: For individuals with no prior comorbidities, depression is associated with a greater risk of developing subsequent physical illness and multimorbidity over time. Thus, depression identifies a population of people who may benefit from early identification, additional screening, and intervention. Further study needs to be done to determine whether interventions to manage and support people with depression can prevent or delay the increased risk of multimorbidity.

Assessing the representativeness of physician and patient respondents to a primary care survey using administrative data.

BACKGROUND: QUALICOPC is an international survey of primary care performance. QUALICOPC data have been used in several studies, yet the representativeness of the Canadian QUALICOPC survey is unknown, potentially limiting the generalizability of findings. This study examined the representativeness of QUALICOPC physician and patient respondents in Ontario using health administrative data. METHODS: This representativeness study linked QUALICOPC physician and patient respondents in Ontario to health administrative databases at the Institute for Clinical Evaluative Sciences. Physician respondents were compared to other physicians in their practice group and all Ontario primary care physicians on demographic and practice characteristics. Patient respondents were compared to other patients rostered to their primary care physicians, patients rostered to their physicians' practice groups, and a random sample of Ontario residents on sociodemographic characteristics, morbidity, and health care utilization. Standardized differences were calculated to compare the distribution of characteristics across cohorts. RESULTS: QUALICOPC physician respondents included a higher proportion of younger, female physicians and Canadian medical graduates compared to other Ontario primary care physicians. A higher proportion of physician respondents practiced in Family Health Team models, compared to the provincial proportion for primary care physicians. QUALICOPC patient respondents were more likely to be older and female, with significantly higher levels of morbidity and health care utilization, compared with the other patient groups examined. However, when looking at the QUALICOPC physicians' whole rosters, rather than just the patient survey respondents, the practice profiles were similar to those of the other physicians in their practice groups and Ontario patients in general. CONCLUSIONS: Comparisons revealed some differences in responding physicians' demographic and practice characteristics, as well as differences in responding patients' characteristics compared to the other patient groups tested, which may have resulted from the visit-based sampling strategy. Ontario QUALICOPC physicians had similar practice profiles as compared to non-participating physicians, providing some evidence that the participating practices are representative of other non-participating practices, and patients selected by visit-based sampling may also be representative of visiting patients in other practices. Those using QUALICOPC data should understand this limited representativeness when generalizing results, and consider the potential for bias in their analyses.

Food intake patterns of homeless youth in Toronto.

OBJECTIVE: To explain the low nutrient intakes of homeless youth in Toronto by looking at their usual food intake patterns and the food they obtained from charitable programs and their own purchases. METHODS: Interviews were conducted with 261 homeless youth (149 male, 112 female), recruited from outdoor locations and drop-in centres in downtown Toronto. Drawing on data from two 24-hour dietary intake recalls, youths' usual food intakes were estimated and compared to Canada's Food Guide recommendations. The nutritional quality of youths' food intakes from charitable meal programs and food purchases was compared. RESULTS: The mean usual food intakes for homeless males and females were well below current recommendations for all four food groups and below the usual intakes of adults, 19-30 years, in the general population. On a given day, youths' mean energy intakes were 1962 +/- 1394 kcal for females and 2163 +/- 1542 kcal for males, with more energy coming from "other foods" than any other food group. Regardless of whether they obtained food from charitable meal programs or purchased it for themselves, youths' mean intakes from the four food groups were very low and most youth consumed no whole grains or dark green or orange vegetables (i.e., foods recommended in Canada's Food Guide). CONCLUSION: The low nutritional quality of youths' food intakes is consistent with the high prevalence of nutrient inadequacies previously documented in this sample. The existing food acquisition strategies of homeless youth appear to be insufficient for them to meet their nutritional needs.