[Reversible mixer].

OBJECTIVES: To review the published literature on interventions aimed at improving physicians' testing practices and propose methodologic standards for these studies and to review selected studies using the PRECEDE framework, a behavioral model that helps categorize interventions based on which behavioral factors are being affected. DATA SOURCES: MEDLINE, EMBASE, and HEALTHStar databases were searched for the years 1966 to January 1, 1998, for English-language articles pertaining to diagnostic testing behavior; bibliographies were scanned to identify articles of potential interest; and researchers in health services, health behavior, and behavior modification were contacted for proprietary and other unpublished articles. STUDY SELECTION: A total of 102 articles were identified that described the results of interventions aimed at changing physicians' testing practices. We included the 49 studies that compared diagnostic testing practices in intervention and control groups. DATA EXTRACTION: Two investigators independently reviewed each article in a blinded fashion using a standard data collection form to obtain a methodologic score and to abstract the key elements of each intervention. DATA SYNTHESIS: On a 38-point methodologic criteria scale, the mean +/- SD score was 13+/-4.4. The desired behavior change was reported in the intervention group in 37 (76%) of 49 studies. Twenty-four (86%) of 28 interventions targeted at many behavioral factors were successful, while 13 (62%) of 21 studies aimed at a single behavioral factor were successful (P=.12). CONCLUSIONS: A majority of interventions to improve physicians' testing practices reported in the literature claimed success, with interventions based on multiple behavioral factors trending toward being more successful. While methodologic flaws hamper drawing strong conclusions from this literature, application of a behavioral framework appears to be useful in explaining interventions that are successful and can facilitate interpretation of intervention results.

Clinical Laboratory Techniques↗

PubMed1998

Effect of population-based interventions on laboratory utilization: a time-series analysis.

CONTEXT: Previous studies have identified methods of decreasing laboratory utilization. However, most were hospital-based, relatively small, single-centered, or of limited duration. OBJECTIVE: To determine the effect of 3 population-based interventions (physician guidelines, laboratory requisition form modification, and changes to funding policy) on laboratory utilization in Ontario. DESIGN: Interventional time-series analysis in which data analysis was based on all claims made to the Ontario Health Insurance Program between July 1, 1991, and April 1997 for laboratory tests affected by the interventions. SETTING: All clinical laboratories (not based in hospitals) in Ontario. INTERVENTIONS: Physician guidelines, modification of laboratory requisition form, and changes in funding policy for the use of the erythrocyte sedimentation rate test (ESR), microscopic urinalysis, tests for renal function, iron stores, serum urea, and serum iron determinations, and tests for thyroid dysfunction (total thyroxine and thyroid-stimulating hormone [TSH]). MAIN OUTCOME MEASURES: Change from 1991 to 1997 in utilization rates of ESR, microscopic urinalysis, serum urea and iron determinations, and tests for total thyroxine and TSH. RESULTS: Age- and sex-standardized rates for laboratory tests unaffected by the interventions were stable during the study period. Utilization of ESR and urea determination decreased by 58% (P<.001) and 57% (P<.001), respectively, after they were removed from the requisition form and guidelines discouraging their use were disseminated. Rates for urinalyses without microscopy increased by 1700% (P<.001), while microscopic urinalysis decreased by 14% (P<.001), after a policy change eliminated microscopic urinalysis from routine urinalysis. Rates of iron determination declined by 80% (P<.001) and ferritin rates increased by 34% (P= .05) when policy changes eliminated iron testing when ordered with ferritin and guidelines advocating ferritin alone for investigating iron deficiency were disseminated. Utilization of total thyroxine testing declined by 96% (P = .02) when the provincial health plan stopped its funding. When TSH was removed from the laboratory requisition form, a 12% decline (P= .03) in its use was observed. Through April 1997, these interventions saved more than 625000 tests or $210400. CONCLUSIONS: The combination of guideline dissemination, laboratory requisition form modification, and changes to funding policy was associated with significant reductions in laboratory utilization.

Clinical Laboratory Techniques↗