Expanding health insurance coverage in vulnerable groups: a systematic review of options

Vulnerable groups are often not covered by health insurance schemes. Strategies to extend coverage in these groups will help to address inequity. We used the existing literature to summarize the options for expanding health insurance coverage, describe which countries have tried these strategies, and identify and describe evaluation studies. We included any report of a policy or strategy to expand health insurance coverage and any evaluation and economic modelling studies. Vulnerable populations were defined as children, the elderly, women, low-income individuals, rural population, racial or ethnic minorities, immigrants, and those with disability or chronic diseases. Forty-five databases were searched for relevant documents. The authors applied inclusion criteria, and extracted data using pre-coded forms, on contents of health insurance schemes or programmes, and used the framework approach to establish categories. Of the 21,528 articles screened, 86 documents were finally included. Descriptions about the USA dominated (72), with only five from Africa, six from Asia and two from South America. We identified six main categories: (1) changing eligibility criteria of health insurance; (2) increasing public awareness; (3) making the premium more affordable; (4) innovative enrollment strategies; (5) improving health care delivery; and (6) improving management and organization of the insurance schemes. All six categories were found in the literature about schemes in the USA, and schemes often included components from each category. Strategies in developing countries were much more limited in their scope. Evaluation studies numbered 25, of which the majority were of time series design. All studies found that the expansion strategies were effective, as assessed by the author(s). In countries expanding coverage, the categories identified from the literature can help policy makers consider their options, implement strategies where it is common sense to do so and establish appropriate implementation monitoring.