Discover a comprehensive review offering critical insights into the design and execution of household surveys on medicine utilization, essential for researchers, policymakers, and public health professionals.
Understanding how communities access, afford, and utilize medicines from the consumer’s perspective is paramount for developing effective health policies and evaluating health systems. However, collecting accurate data on medicine use, especially in low and middle-income countries where computerized systems are scarce, presents significant methodological challenges. Self-reported data, gathered through direct interviews, is prone to reporting bias, making a carefully designed methodology crucial.
Bertoldi et al.’s seminal 2008 article, “A descriptive review of the methodologies used in household surveys on medicine utilization,” published in BMC Health Services Research, addresses these challenges head-on. This systematic review provides a vital resource by describing the methodological and analytical aspects of quantitative household studies on medicine utilization, analyzing employed methodologies qualitatively, and offering actionable recommendations for future research in the field. Its findings are indispensable for researchers aiming to improve the quality of medicine use data and to navigate the complexities of study planning and analysis.
Key Highlights of the Review:
The authors conducted a rigorous systematic review of original papers published between 1995 and 2008, where the household was a sampling unit. Searching Medline/Pubmed, Scielo, and Lilacs, and meticulously applying specific inclusion and exclusion criteria, they identified 61 relevant studies.
The review reveals several key trends and methodological practices among medicine utilization studies:
- Geographic Focus and Design: The majority of studies (64.0%) were conducted in Europe and North America, predominantly employing a cross-sectional approach.
- Data Collection Methods: Over 80% of studies relied on face-to-face interviews for data collection.
- Recall Period: The most frequently used recall period was 14–15 days, though the range varied broadly from one day to two years [3, 16, Figure 1]. Studies on chronic diseases often asked about current use without a defined reference period, while others differentiated recall periods for acute versus chronic medicines.
- Data Validation: A significant proportion (59%) of studies trained interviewers to request medicine packaging from subjects, enhancing data accuracy. However, medical prescriptions were requested far less frequently (15%).
- Questionnaire Design: Approximately 75% of studies utilized open-ended questions to investigate medicine use. The Anatomical Therapeutic Chemical (ATC) classification system was the most common for pharmacological groups, though 42.5% of studies did not specify their classification system.
- Analytical Denominators: Most studies used individuals as the denominator in their analyses.
Crucial Methodological Insights and Recommendations for Future Studies:
The authors delve into critical methodological aspects, providing invaluable guidance:
- Optimizing Recall Period: While there’s no single “ideal” recall period, the authors highlight its profound impact on reported prevalence and accuracy. They suggest that 14–15 days is a recommended period for comparison with existing literature. Longer periods can lead to underreporting, particularly for self-prescribed medicines, as recall accuracy decreases.
- Choosing Administration Mode: Face-to-face interviews are strongly recommended, especially in low and middle-income countries, due to their higher response rates and the practical limitations (e.g., low telephone coverage, high illiteracy) of other methods like telephone or postal surveys.
- Crafting Effective Questions: Researchers should use simple, technically correct terminology and clearly define “medicine use” to respondents. Special attention should be paid to prompting for seemingly “less important” medicines like analgesics, natural products, or topical treatments, which are often underreported. Open-ended questions are preferred for evaluating overall medicine utilization.
- Utilizing Proxy Information: For studies involving elderly subjects, who may have higher medicine utilization but difficulty providing accurate information, interviewing close relatives or caregivers (proxies) is recommended to avoid underestimating prevalence.
- Leveraging Packaging and Prescriptions: Requesting to see medicine packaging is a highly valuable strategy for validating data and aiding recall in household studies. While less common, requesting prescriptions can further qualify and validate collected data.
- Standardizing Classification and Denominators: Authors are urged to explicitly state the pharmacological group classification system used (e.g., ATC) and the denominator (individuals vs. medicines) employed in analyses, as these choices significantly affect data interpretation and comparability across studies.
Conclusion:
This comprehensive review serves as a critical update for researchers on current methodological standards in household medicine utilization surveys. It not only summarizes existing practices but also provides thoughtful recommendations that can significantly improve the quality of data obtained and guide the planning and analysis of future studies. The authors advocate for greater standardization of methods and more detailed reporting to facilitate international comparisons and replication.
Reference for the Article:
Bertoldi, A. D., Barros, A. J. D., Wagner, A., Ross-Degnan, D., & Hallal, P. C. (2008). A descriptive review of the methodologies used in household surveys on medicine utilization. BMC Health Services Research, 8(1), 222. https://doi.org/10.1186/1472-6963-8-222