Background: The objectives of this integrative review were to critically examine the overall state of the current evidence on the relationship between hand hygiene interventions and the incidence of health care-associated infections (HCAIs) in acute care and long-term care settings, and offer recommendations for future directions in the field based on our findings.
Methods: We searched for original research and reviews of research published between January 1, 1996, and July 31, 2006. Studies were identified through the electronic databases Medline, CINAHL, EMBASE, PUBMED, the Cochrane Library, and through expert consultation. Our comprehensive search strategy included all English articles for which hand hygiene or handwashing-related terms were combined with HCAIs. All studies that investigated a relationship between hand hygiene practices and HCAIs in acute care facilities were considered. These hand hygiene practices included the initiation of multimodal hand hygiene initiatives, the introduction of alcohol sanitizers, the implementation or changes of the infection control practices or infection control policies, and other organizational interventions. Studies only examining hand hygiene compliance, efficacy of alcohol hand gels, plain soap, and antimicrobial soap in reducing bacteria count recovered from hands were excluded.
Results: Of the 1120 articles retrieved, 35 publications, including 4 reviews of research discussed at the outset of this article, met our inclusion criteria. The remaining 31 eligible original studies included 18 (58.07%) before and after studies without control groups, 4 (12.90%) before and after studies with a control group, 3 (9.68%) cohort studies with no control group, 4 (12.90%) cohort studies with a control group, and 2 (6.45%) randomized trials. Over 50% (16 or 31) of the studies were conducted in the U.S. Two independent reviewers conducted independent evaluations of all eligible studies, critiquing and scoring each study using a rating scale for examining the fatal flaws of quasi-experimental and before and after studies.
Conclusions: There is a lack of rigorous evidence linking specific hand hygiene interventions with the prevention of HCAIs. The varied nature of the interventions used and the diverse factors affecting the acquisition of HCAIs make it difficult to show the specific effect of hand hygiene alone. The most frequent methodologies currently used in this research area are before and after observational studies without a control comparison group. Based on these findings, we recommend that researchers used a modified version of Larson's 2005 criteria to guide the design and conduct of future before and after observational studies in this area. We also argue that as we accumulate stronger evidence of which interventions are most effective, we need to develop additional research approaches to study how organizations succeed and fail in fostering the uptake of evidence-based hand hygiene interventions.