Abstract
BACKGROUND: There is evidence to suggest that decision aids improve a number of patient outcomes. However, little is known about the progression of research effort in this area over time. This literature review examined the volume of research published in 2000, 2007 and 2014 which tested the effectiveness of decision aids in improving cancer patient outcomes, coded by cancer site and decision type being targeted. These numbers were compared with the volume of research examining the effectiveness of strategies to increase the adoption of decision aids by healthcare providers. METHODS: A literature review of intervention studies was undertaken. Medline, Embase, PsychInfo and Cochrane Database of Systematic Reviews were searched. The search was limited to human studies published in English, French, or German. Abstracts were assessed against eligibility criteria by one reviewer and a random sample of 20 % checked by a second. Eligible intervention studies in the three time periods were categorised by: i) whether they tested the effectiveness of decision aids, coded by cancer site and decision type, and ii) whether they tested strategies to increase healthcare provider adoption of decision aids. RESULTS: Over the three time points assessed, increasing research effort has been directed towards testing the effectiveness of decision aids in improving patient outcomes (p < 0.0001). The number of studies on decision aids for cancer screening or prevention increased statistically significantly (p < 0.0001) whereas the number of studies on cancer treatment did not (p = 1.00). The majority of studies examined the effectiveness of decision aids for prostate (n = 10), breast (n = 9) or colon cancer (n = 7). Only two studies assessed the effectiveness of implementation strategies to increase healthcare provider adoption of decision aids. CONCLUSIONS: While the number of studies testing the effectiveness of decision aids has increased, the majority of research has focused on screening and prevention decision aids for only a few cancer sites. This neglects a number of cancer populations, as well as other areas of cancer care such as treatment decisions. Also, given the apparent effectiveness of decision aids, more effort needs to be made to implement this evidence into meaningful benefits for patients.