In High-Deductible Health Plans and Prevention, published in the April issue of Annual Review of Public Health, Mazurenko, Buntin and Menachemi look at existing studies focused on the effects of HDHPs on healthcare utilization, specifically in the context of preventive services.
The intended purpose of HDHPs is to shift costs to patients and thereby push them towards “higher-value health care decisions.” But the unintended consequences include skipping out on necessary care. What’s odd about HDHPs and preventive care is that preventive visits are typically fully covered under HDHP plans. Put another way, why would patients avoid ‘free’ services? A few possible reasons have been considered, and additional research is needed to understand why this gap exists and how to close it. (As an aside, two of the five possible reasons for the discrepancy mentioned by the authors come down to a lack of understanding on the part of patients regarding what is covered and how services are billed – more patient education and health literacy, please!)
Mazurenko and colleagues reviewed numerous studies grouped into five broad methodological categories. These ranged from “patient vignettes” (hypothetical situations used to gauge clinician responses) to randomized controlled trials. The primary purpose of the paper was not to determine whether HDHPs alter utilization of care, but to better understand the strengths and weaknesses of different methods used to study that relationship. The paper also points out differences in results between studies using similar methods. Even in what they deem the strongest approach, a blend between a randomized controlled trial and more anecdotal approaches called quasi-experimental design, results varied. Differences in the “study populations, data sources, types of preventive care services, and various time horizons” led to a majority of reports finding changes in utilization patterns under HDHPs, but there were several that did not.
In the end, the authors conclude that yes, the weight of evidence supports the conclusion that utilization of preventive screening drops under HDHPs, but whether those results extend to all preventive services isn’t clear.
The paper is useful for two primary reasons: First, it breaks down the different methods used to study the question of HDHPs, essentially offering a side-by-side comparison of the strengths and weaknesses of each approach. Secondly, it highlights the importance of understanding the limitations of any given dataset when taking action based on that data. For example, it would be problematic to make public health decisions based on a single study, because most studies are only able to look at a relatively narrow (sub)population and or limited set of outcomes.