Interventions to Reduce the Overuse of Imaging for Pulmonary Embolism: A Systematic Review
BACKGROUND: Imaging use in the diagnostic workup of pulmonary embolism (PE) has increased markedly in the last 2 decades. Low PE prevalence and diagnostic yields suggest a significant problem of overuse.
PURPOSE: The purpose of this systematic review is to summarize the evidence associated with the interventions aimed at reducing the overuse of imaging in the diagnostic workup of PE in the emergency department and hospital wards.
DATA SOURCES: PubMed, MEDLINE, Embase, and EBM Reviews from 1998 to March 28, 2017.
STUDY SELECTION: Experimental and observational studies were included. The types of interventions, their efficacy and safety, the impact on healthcare costs, the facilitators, and barriers to their implementation were assessed.
DATA SYNTHESIS: Seventeen studies were included assessing clinical decision support (CDS), educational interventions, performance and feedback reports (PFRs), and institutional policy. CDS impact was most comprehensively documented. It was associated with a reduction in imaging use, ranging from 8.3% to 25.4%, and an increase in diagnostic yield, ranging from 3.4% to 4.4%. The combined implementation of a CDS and PFR resulted in a modest but significant increase in the adherence to guidelines. Few studies appraised the safety of interventions. There was a lack of evidence concerning economic aspects, facilitators, and barriers.
CONCLUSIONS: A combined implementation of an electronic CDS and PFRs is more effective than purely educational or policy interventions, although evidence is limited. Future studies of high-methodological quality would strengthen the evidence concerning their efficacy, safety, facilitators, and barriers.
© 2018 Society of Hospital Medicine
The last 2 decades have seen a dramatic rise in the use of medical imaging in general,1,2 as well as in the diagnostic workup of pulmonary embolism (PE) more specifically, since the introduction of multidetector row computed tomography pulmonary angiography (CTPA) in 1998.3 From 1999 to 2010, the proportions of emergency department (ED) visits associated with a diagnosis of PE and admissions for PE have increased markedly in the United States, where the situation has been well documented.4,5 A 14-fold increase in the use of CTPA was observed in health maintenance organizations from 2001 to 2008.3 A significant increase in the probability of having a diagnosis of PE in the ED was reported, likely because of increased access to CTPA, from 2001 to 2010.4 With a prevalence of 2% or less in the ED, diagnostic yields as low as 5% suggest a significant problem of overuse.6,7
Strategies have been proposed to improve the appropriateness of imaging in the detection of PE, and these rely on the use of a validated clinical decision rule (CDR) to assess the pretest probability of the diagnosis. The purpose of this systematic review is to summarize the evidence associated with interventions aimed at reducing the overuse of imaging in the diagnostic workup of PE in the ED and hospital wards. Specifically, the types of interventions, their clinical effectiveness, as well as possible harms will be assessed. A secondary objective is to appraise the impact of these interventions on healthcare costs as well as the facilitators and barriers to their implementation.
METHODS
Inclusion Criteria
Targeted settings were EDs and inpatient services of adult tertiary and quaternary care hospitals. The search addressed interventions aimed at reducing the overuse of imaging in the diagnostic workup for PE. The comparators were usual care or another type of related intervention. The main outcomes considered were the use of imaging, diagnostic yield, radiation dose, adherence to guidelines to a quality measure, safety, and costs; both experimental and observational studies were included.
Literature Search
A systematic literature search in the following electronic databases was performed: PubMed, MEDLINE, Embase, and EBM Reviews (Cochrane, ACP Journal Club, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register, Cochrane Health Technology Assessment, and the NHS Economic Evaluation Database). The reference period was from 1998 to March 28, 2017, and publications in English and French were searched. The detailed search strategy, adapted to each of the databases, appears in supplemental Appendix 1.
Study Selection and Data Extraction
One author (SD) reviewed the titles of the selected articles and excluded those that obviously did not satisfy the inclusion criteria. Then, 2 authors (SD and LL) independently reviewed the titles and abstracts of the remaining articles. They reviewed the full manuscript of potentially relevant articles for inclusion. Disagreements that could not be resolved by discussion would have been arbitrated by a third author (CCL); however, no such disagreement occurred.
Quality and Risk of Bias Assessment
For experimental or quasiexperimental studies that involved an intervention group and a control group, the criteria proposed by the Cochrane collaborative for the evaluation of bias were used.8 For studies using a before and after design, the following main biases associated with such designs were assessed: history effect, maturation bias, testing bias, regression to the mean, and conditioning bias.9
Data Extraction and Synthesis
Data pertaining to efficacy, safety, costs, and facilitators and barriers to the implementation of interventions were extracted from the studies. The research process adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 checklist.10 In view of the heterogeneity of the studies, a narrative synthesis was produced in accordance with the methodology proposed by Popay et al.11 The review protocol was registered in PROSPERO (this registry can be consulted at the following URL address: https://www.crd.york.ac.uk/PROSPERO/).
RESULTS
The search screened 2814 records after the removal of duplicates and studies published before 1998. The figure illustrates the literature selection process.12 Seventeen studies were included in the review following appraisal. Most of the studies (15/17) evaluated interventions in the ED,7,13-26 while the remaining studies (2/17) were conducted in clinical wards of acute care hospitals.27,28 Thirteen studies were conducted in the United States, 3 in Australia, and 1 in Europe. Four types of interventions were identified in the selected studies: electronic clinical decision support (CDS) (8/17), educational interventions (7/17), performance feedback reports (PFRs) (1/17), and an institutional clinical pretest policy (1/17). In 10 of the studies, the proposed intervention was mandatory.
