Designing a search strategy to identify and retrieve articles on evidence-based health care using MEDLINE

The practice of evidence-based health care requires that information on methodology be identified from databases such as MEDLINE. Up until this year there have been no designated medical subject headings (MeSH) for evidence-based health care. 'EVIDENCE-BASED MEDICINE' appears as a MeSH term from 1997. The absence of designated MeSH for this concept prior to 1997 provides a challenge to the searcher. This paper describes the creation of a MEDLINE search strategy to retrieve articles on the methods of evidence-based health care published prior to the introduction of the new term, where an optimal combination of free-text and MeSH terms is required to identify relevant material. The study examines both free-text and subject heading searching and attempts an optimal balance of sensitivity and specificity. It begins by examining separate free-text and subject heading searches. Sensitivity of the subject heading search was 33% and specificity 80%, while the free-text search produced a sensitivity of 50% and a specificity of 67%. The final strategy, combining both approaches, was more successful with sensitivity reaching between 82 and 90% and specificity 83%. It is therefore possible to devise a search strategy to retrieve articles on the methods of evidence-based health care with relatively successful rates of sensitivity and specificity. The limitations of MEDLINE, however, necessitate the use of additional approaches in identifying articles on the methods of evidence-based health care.     

The diagnostic value of macroscopic haematuria in diagnosing urological cancers: a meta-analysis

OBJECTIVE: To evaluate the diagnostic value of macroscopic haematuria for the diagnosis of urological cancers in primary care as well as referred patients. METHOD: Systematic review of published reports, identified by a search on Medline and FAMLI and by screening of reference lists of selected papers. The evaluation of the sensitivity was based on patients with proven cancer of the kidney, ureter, bladder, urethra or prostate. The evaluation of the positive predictive value (PPV) was based on patients complaining to their physicians of macroscopic haematuria. RESULTS: No study executed in a primary care setting was included. In referred patients the pooled sensitivity of macroscopic haematuria for bladder cancer, based on seven remarkably homogeneous studies, was 0.83 (95% CI = 0.80-0.85). For ureteral cancer, this was 0.66 (95% CI = 0.53-0.77) based on four reports and for renal cancer 0.48 (95%) CI = 0.36-0.60) based on three studies. The pooled PPV of haematuria for urological cancer was 0.22 (0.17-0.27) in referred patients. Most malignancies detected were bladder cancers (255/317). PPV was highest in patients aged 40 or more at 0.41 (95% CI = 0.10-0.78). CONCLUSIONS: The advice that all patients with macroscopic haematuria should receive a thorough diagnostic programme seems justified in a specialized setting, dealing with referred patients. At this moment no data are available to support or discourage a similar policy for GPs. Prospective studies on the diagnostic value of macroscopic haematuria for urological cancer in a primary care setting are urgently needed.      

Accuracy of physical diagnostic tests for assessing ruptures of the anterior cruciate ligament: a meta-analysis

OBJECTIVE: This systematic review summarizes the evidence on the accuracy of tests for assessing ACL ruptures of the knee. SEARCH STRATEGY: A computerized search of MEDLINE (1966-2003) and EMBASE (1980-2003) with additional reference tracking. SELECTION CRITERIA: Articles included were written in English, French, German, or Dutch, and addressed the accuracy of at least 1 physical diagnostic test for ACL rupture, using arthrotomy, arthroscopy, or magnetic resonance imaging as the gold standard. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected studies, assessed the methodological quality, and abstracted data using a standardized protocol. We calculated sensitivity, specificity, and likelihood ratios for each test and summary estimates, when appropriate and possible. MAIN RESULTS: Seventeen studies met the inclusion criteria. None assessed the index test and reference test independently (with blinding), and all but 2 displayed verification bias. Study results were heterogeneous. The pivot shift test seems to have favorable positive predictive value, and the Lachman test has good negative predictive value. The anterior drawer test is of unproven value. CONCLUSIONS: Reliable data are rare regarding the accuracy of physical diagnostic tests for ACL ruptures, especially in a primary care setting. For the time being, history taking and physical examination, albeit of limited use, should be considered with individual patient demands to provide the basis for further evaluation.     

Publications on diagnostic test evaluation in family medicine journals: an optimal search strategy

Search strategies for articles reporting on diagnostic test evaluations have been subjected to less research than those in the domain of clinical trials. We set out to develop an optimal search strategy for publications on diagnostic test evaluations in general, that could be added to keywords describing the specific diagnostic test at issue. Nine Family Medicine journals were searched from 1992 through 1995 for primary publications on diagnostic test evaluation by hand searching and a Medline search strategy published earlier. Additionally, new search strategies have been developed with stepwise logistic regression, using Mesh terms and free text words related to diagnosis and test evaluation as independent variables. Hand searching identified 75 primary publications on diagnostic test evaluation from a total of 2467 primary publications. The previously published search strategy had a sensitivity of 73%, a specificity of 94%, and a positive predictive value of 29%. The most accurate new search strategy had a sensitivity of 80.0% (60/75; 95% CI: 71.0-89.1), a specificity of 97.3% (2327/2392; 95% CI; 96.6-97.9%), a positive predictive value of 48% (95% CI: 40-56) and diagnostic odds ratio of 149. All four new strategies used the Mesh term "sensitivity and specificity" (exploded with the Mesh terms "predictive value" and "ROC")and cumulatively added the text words "specificity," "false negative," "accuracy," and "screening." The search strategy using the Mesh term "sensitivity and specificity" (exploded) and the text words "specificity," "false negative," and "accuracy" has both higher sensitivity and specificity than the previously published strategy. The increase in specificity in three strategies reduces the absolute number of false-positive articles that have to be screened by 50-75%, compared to the number of false positives in the earlier strategy.     

The diagnostic value of digital rectal examination in primary care screening for prostate cancer: a meta-analysis

OBJECTIVE: This systematic review examines the diagnostic value of the digital rectal examination (DRE) for the diagnosis of prostate cancer. METHOD: Only studies relating to unselected populations and using either biopsy or surgery as the reference standard were included. The methodological quality of the studies was used in an attempt to explain differences between studies. RESULTS: Fourteen studies were eligible for selection, of which five complied with the predetermined list of 'good-quality' requirements. Between study heterogeneity was high, even within the group of high-quality studies, and could not be explained by the registered indicators of methodological quality. CONCLUSIONS: In this setting, the DRE appears to be a test with a high specificity and negative predictive value, but a low sensitivity and positive predictive value. Neither a positive nor a negative test result is sufficient to enable conclusions without further confirmation.     

The accuracy of physical diagnostic tests for assessing meniscal lesions of the knee: a meta-analysis

OBJECTIVE: Our systematic review summarizes the evidence about the accuracy of those tests. SEARCH STRATEGY: We performed a literature search of MEDLINE (1966-1999) and EMBASE (1988-1999) with additional reference tracking. SELECTION CRITERIA: Articles written in English, French, German, or Dutch, that addressed the accuracy of at least one physical diagnostic test for meniscus injury with arthrotomy, arthroscopy, or magnetic resonance imaging as the gold standard were included. We excluded studies if no reference group or only test-positives had been included, if the study pertained to cadavers only, or if only physical examination under anesthesia was considered. DATA COLLECTION/ANALYSIS: Two reviewers independently selected studies, assessed the methodologic quality, and abstracted data using a standardized protocol. We calculated sensitivity, specificity, and likelihood ratios for each test, and summary estimates when appropriate and possible. MAIN RESULTS: Of 402 identified studies, 13 met the inclusion criteria. The results of the index and reference tests were assessed independently (blindly) of each other in only 2 studies, and in all studies verification bias seemed to be present. The study results were highly heterogeneous The summary receiver operating characteristic curves of the assessment of joint effusion, the McMurray test and joint line tenderness indicated little discriminative power for these tests. Only the predictive value of a positive McMurray test was favorable. CONCLUSIONS: The methodologic quality of studies addressing the diagnostic accuracy of meniscal tests was poor, and the results were highly heterogeneous. The poor characteristics indicate that these tests are of little value for clinical practice.     

Diagnostic test systematic reviews: Bibliographic search filters (“Clinical Queries”) for diagnostic accuracy studies perform well

BackgroundSystematic reviews of health care topics are valuable summaries of all pertinent studies on focused questions. However, finding all relevant primary studies for systematic reviews remains challenging.ObjectivesTo determine the performance of the Clinical Queries sensitive search filter for diagnostic accuracy studies for retrieving studies for systematic reviews.MethodsWe compared the yield of the sensitive Clinical Queries diagnosis search filter for MEDLINE and EMBASE to retrieve studies in diagnostic accuracy systematic reviews reported in ACP Journal Club in 2006.ResultsTwelve of 22 diagnostic accuracy reviews (452 included studies) met the inclusion criteria. After excluding 11 studies not in MEDLINE or EMBASE, 95% of articles (417 of 441) were captured by the sensitive Clinical Queries diagnosis search filter (MEDLINE and EMBASE combined). Of 24 studies not retrieved by the filter, 22 were not diagnostic accuracy studies. Reanalysis of the Clinical Queries filter without these 22 nondiagnosis articles increased its performance to 99% (417 of 419). We found no substantive impact of the two articles missed by the Clinical Queries filter on the conclusions of the systematic reviews in which they were cited.ConclusionThe sensitive Clinical Queries diagnostic search filter captured 99% of articles and 100% of substantive articles indexed in MEDLINE and EMBASE in diagnostic accuracy systematic reviews.     

Hospitalizations due to ambulatory care sensitive conditions: selection of diagnostic codes for Spain

BACKGROUND: Hospitalisations due to Ambulatory Care Sensitive Conditions (ACSC) are considered an indicator to measure the use of hospital services because of health conditions that could have been prevented and controlled by primary health care. The objective of this study is to select the list of diagnostic codes to assess the performance of primary health care in Spain. METHODS: The five criteria proposed by Weissman and Solberg, to select an appropriate indicator, were applied to a first list of 87 ACSC diagnostic codes identified through bibliographic search. Information on two main criteria-whether care for a health condition was a primary health care role and whether hospitalisation was needed once the health problem occurred was obtained by means of the Delphi technique. A group of 44 experts gathered together for the study. For the remaining criteria, information came from the results of the Pilot study on hospitalisations due to ACSC in Catalonia, Spain. Meeting the five criteria was the criterion selected to evaluate the solving ability of primary health care. RESULTS: a) from the Delphi group: 42 (95.4%) participants completed the three rounds. The question on whether the care of the selected health conditions was responsibility of primary health care reached a high level of consensus (between 86.1 and 100%). The consensus on the need for hospitalisation was lower, from 75.7 to 88.6%, moreover, 5 diagnostic codes did not reach the established consensus, and b) from the ACSC selection process: five diagnostic codes did not meet the criteria and were excluded. Out of the remaining 82, all them were considered as health problems to be cared for at primary level and in 37 cases hospitalisation was considered always as necessary. Thirty-five diagnostic codes, that met the five criteria, represented the set of ACSC diagnostic codes in our setting. CONCLUSIONS: A set of 35 diagnostic codes of ACSC, adapted to our setting, is proposed to evaluate primary health care performance. The selected codes reduce significantly the limitations that stem from hospital admission criteria due to patient clinical characteristics, variations in hospital medical practice, and hospital admission policies.     

Evaluating detection and diagnostic decision support systems for bioterrorism response

We evaluated the usefulness of detection systems and diagnostic decision support systems for bioterrorism response. We performed a systematic review by searching relevant databases (e.g., MEDLINE) and Web sites for reports of detection systems and diagnostic decision support systems that could be used during bioterrorism responses. We reviewed over 24,000 citations and identified 55 detection systems and 23 diagnostic decision support systems. Only 35 systems have been evaluated: 4 reported both sensitivity and specificity, 13 were compared to a reference standard, and 31 were evaluated for their timeliness. Most evaluations of detection systems and some evaluations of diagnostic systems for bioterrorism responses are critically deficient. Because false-positive and false-negative rates are unknown for most systems, decision making on the basis of these systems is seriously compromised. We describe a framework for the design of future evaluations of such systems.     

The value of the CAGE in screening for alcohol abuse and alcohol dependence in general clinical populations: a diagnostic meta-analysis

OBJECTIVE: To perform a meta-analysis to assess diagnostic characteristics of the CAGE in screening for alcohol abuse or dependence in a general clinical population and to test a new method for pooling of ROC curves. METHODS: Medline search performed over the period 1/1/1974 to 31/12/2001. MEASUREMENT: Calculation of diagnostic values. RESULTS: We identified 35 articles using the DSM criteria as the gold standard to test the diagnostic value of the CAGE. Only 10 studies could be included for the meta-analysis. With a cutoff point > or =2, the pooled sensitivity is far better in inpatients (0.87) than in primary care patients (0.71) or ambulatory patients (0.60). The pooled specificity also differs for each group. The likelihood ratios seem to be relatively constant over the populations (overall LR+:3.44;LR-:0.18). We calculated a pooled AUC of 0.87 (95% CI 0.85-0.89). At low specificity values, the sensitivity was homogeneous over the studies, and at a low sensitivity, the specificity was heterogeneous. CONCLUSION: The diagnostic value of the CAGE is of limited value using this test for screening purposes at his recommended cutpoint of > or =2.     

Development of a highly sensitive search strategy for the retrieval of reports of controlled trials using PubMed

OBJECTIVE: To develop, through revision of the Cochrane Collaboration search strategy for OVID-MEDLINE, a highly sensitive search strategy to retrieve reports of controlled trials using PubMed. METHODS: The original highly sensitive Cochrane strategy was revised to take into account additional Medical Subject Headings (MeSH) and other terminology as well as the current unique features of PubMed. We compared the retrieval of the revised strategy with that of the original Cochrane strategy before and after translation of the strategies into PubMed format. Finally, we used a gold standard database of reports of controlled trials identified by electronic and hand search of selected journals to test the revised strategy in PubMed format. RESULTS: The revised strategy included a search statement modified for increased precision, and added 'Cross-over Studies' as a MeSH term and the term 'latin square' as a text word. Compared to the original Cochrane strategy, the revised strategy identified 53 additional reports of controlled trials accessing MEDLINE through OVID. When the revised strategy and original Cochrane strategy were translated into PubMed format, the revised strategy retrieved 90 reports of controlled trials not identified by the original strategy. Finally, the revised strategy in PubMed format retrieved all of the reports of controlled trials in the gold standard database. Ninety-eight per cent of the gold standard reports of controlled trials were retrieved by Phase 1 of the optimal PubMed search strategy. CONCLUSIONS: Failure to identify all relevant trials for systematic review could result in bias. We developed a highly sensitive search strategy for the retrieval of reports of controlled trials for use with PubMed that retrieves more relevant citations (greater sensitivity) and fewer non-relevant citations (greater precision) than the original Cochrane search strategy.     

Should patients with abnormal liver function tests in primary care be tested for chronic viral hepatitis: cost minimisation analysis based on a comprehensively tested cohort

Background

Clinicians should be aware of the diagnostic values of various symptoms, signs and antecedents. This information is particularly important in primary care settings, where sophisticated diagnostic approaches are not always feasible. The aim of the study is to determine the probability that various symptoms, signs, antecedents and tests predict urinary tract infection (UTI) in women.

Methods

We conducted a systematic search of the MEDLINE and EMBASE databases to identify articles published in all languages through until December 2008. We particularly focused on studies that examined the diagnostic accuracy of at least one symptom, sign or patient antecedent related to the urinary tract. We included studies where urine culture, a gold standard, was preformed by primary care providers on female subjects aged at least 14 years. A meta-analysis of the likelihood ratio was performed to assess variables related to the urinary tract symptoms.

Results

Of the 1, 212 articles identified, 11 met the selection criteria. Dysuria, urgency, nocturia, sexual activity and urgency with dysuria were weak predictors of urinary tract infection, whereas increases in vaginal discharge and suprapubic pain were weak predictors of the absence of infection. Nitrites or leukocytes in the dipstick test are the only findings that clearly favored a diagnosis of UTI.

Conclusions

Clinical findings do not aid in the diagnosis of UTI among women who present with urinary symptoms. Vaginal discharge is a weak indicator of the absence of infection. The urine dipstick test was the most reliable tool for detecting UTI.     

Antibiotic use and resistance in long term care facilities

IntroductionThe common occurrence of infectious diseases in nursing homes and residential care facilities may result in substantial antibiotic use, and consequently antibiotic resistance. Focusing on these settings, this article aims to provide a comprehensive overview of the literature available on antibiotic use, antibiotic resistance, and strategies to reduce antibiotic resistance.MethodsRelevant literature was identified by conducting a systematic search in the MEDLINE and EMBASE databases. Additional articles were identified by reviewing the reference lists of included articles, by searching Google Scholar, and by searching Web sites of relevant organizations.ResultsA total of 156 articles were included in the review. Antibiotic use in long term care facilities is common; reported annual prevalence rates range from 47% to 79%. Part of the prescribed antibiotics is potentially inappropriate.The occurrence of antibiotic resistance is substantial in the long term care setting. Risk factors for the acquisition of resistant pathogens include prior antibiotic use, the presence of invasive devices, such as urinary catheters and feeding tubes, lower functional status, and a variety of other resident- and facility-related factors. Infection with antibiotic-resistant pathogens is associated with increased morbidity, mortality, and health care costs.Two general strategies to reduce antibiotic resistance in long term care facilities are the implementation of infection control measures and antibiotic stewardship.ConclusionThe findings of this review call for the conduction of research and the development of policies directed at reducing antibiotic resistance and its subsequent burden for long term care facilities and their residents.     

Comparison of the diagnostic accuracy of a rapid immunochromatographic test and the rapid plasma reagin test for antenatal syphilis screening in Mozambique

OBJECTIVE: Programmes to control syphilis in developing countries are hampered by a lack of laboratory services, delayed diagnosis, and doubts about current screening methods. We aimed to compare the diagnostic accuracy of an immunochromatographic strip (ICS) test and the rapid plasma reagin (RPR) test with the combined gold standard (RPR, Treponema pallidum haemagglutination assay and direct immunofluorescence stain done at a reference laboratory) for the detection of syphilis in pregnancy. METHODS: We included test results from 4789 women attending their first antenatal visit at one of six health facilities in Sofala Province, central Mozambique. We compared diagnostic accuracy (sensitivity, specificity, and positive and negative predictive values) of ICS and RPR done at the health facilities and ICS performed at the reference laboratory. We also made subgroup comparisons by human immunodeficiency virus (HIV) and malaria status. FINDINGS: For active syphilis, the sensitivity of the ICS was 95.3% at the reference laboratory, and 84.1% at the health facility. The sensitivity of the RPR at the health facility was 70.7%. Specificity and positive and negative predictive values showed a similar pattern. The ICS outperformed RPR in all comparisons (P<0.001). CONCLUSION: The diagnostic accuracy of the ICS compared favourably with that of the gold standard. The use of the ICS in Mozambique and similar settings may improve the diagnosis of syphilis in health facilities, both with and without laboratories.     

识别诊断试验准确性系统综述的方法学异质性

目的 分析诊断试验系统综述的方法学异质性来源。方法 通过检索2008年1月1日至2012年12月31日发表在Medline、Embase、Cochrane(CDSR和DARE)数据库中关于诊断试验准确性(DTA)的Meta分析文献,纳入了至少包含10篇原始研究的Meta分析。两名人员独立地对研究特点以及原始研究的数据进行提取,使用混合线性模型对14种潜在的方法学异质性因素来源进行探讨,进而计算出14种异质性因素的诊断比值比(DOR)之比(RDOR)值及其95% CI,从而判断其异质性大小和方向。结果 最终纳入了23篇DTA的系统综述,涵盖550篇原始研究。纳入的550篇原始研究的质量良好。单因素混合线性模型分析显示,"金标准是否足够准确"和"金标准与待检试验是否相互独立"是DTA系统综述的异质性来源。多因素混合线性模型分析显示,金标准不准确的诊断试验,其DOR合并值低于金标准足够准确的诊断试验,RDOR=0.018 6(95% CI:0.001 0~0.358 5);金标准与待检试验不独立的诊断试验,其DOR合并值高于金标准与待检试验相互独立的诊断试验,RDOR=2.396 6(95% CI:1.242 8~4.622 7)。结论 对于诊断试验系统综述,原始研究的金标准是否足够准确、金标准与待检试验是否相互独立为其方法学异质性的来源。     

The quality and impact of MEDLINE searches performed by end users

Evidence suggests that MEDLINE is becoming an important clinical tool that can improve the care and health of patients. Efforts to improve the quality and impact of end-user searching are needed and ongoing. End users are completing many MEDLINE searches. They appreciate and value training along with feedback on their searching techniques. Practice, is however, the biggest single factor in improving the quality of searching. Key roles for the library in end-user searching include, providing the most effective MEDLINE access possible to the maximum number of users, and providing training that includes feedback and practice opportunities. System-wide advances in structured abstracts, indexing, system design, informatics research and the literature itself will make searching easier and more effective in the future. More important than the quality of search results per se is the impact that end-user searches have on patient care and patient outcomes. Growing evidence shows that both patient care and patient outcomes are improved by end-user searches.     

Does continuity of care improve patient outcomes?

OBJECTIVE: Continuity of care is a cornerstone of primary care that has been promoted by recent trends in medical education and in the way health care delivery is organized. We sought to determine the effect of sustained continuity of care (SCOC) on the quality of patient care. DATA SOURCES: We conducted a systematic review of all articles in Medline (January 1966 to January 2002), Educational Resources Information Center (ERIC), and PSYCH INFO using the terms "continuity of care" or "continuity of patient care." We identified additional titles of candidate articles by reviewing the bibliographies of articles from our original MEDLINE search, contacting experts in primary care, health care management, and health services research, and by reviewing bibliographies of textbooks of primary care and public health. STUDY SELECTION AND DATA EXTRACTION: Two investigators (MDC, SHJ) independently reviewed the full text to exclude articles that did not fulfill search criteria. Articles excluded were those that focused on physicians-in-training, on SCOC in a non-primary care setting, such as an inpatient ward, or on transitions from inpatient to the outpatient setting. We also excluded articles that did not correlate SCOC to a quality of care measure. DATA SYNTHESIS: From 5070 candidate titles, we examined the full text of 260 articles and found 18 (12 cross-sectional studies, 5 cohort studies and 1 randomized controlled trial) that fulfilled our criteria. Five studies focused on patients with chronic illness (eg, asthma, diabetes). RESULTS: No studies documented negative effects of increased SCOC on quality of care. SCOC is associated with patient satisfaction (4 studies), decreased hospitalizations and emergency department visits (7 studies), and improved receipt of preventive services (5 studies). CONCLUSIONS: SCOC improves quality of care, and this association is consistently documented for patients with chronic conditions. Programs to promote SCOC may best maximize impact by focusing on populations with chronic conditions.     

Asking For Help is Helpful: Validation of a Brief Lifestyle and Mood Assessment Tool in Primary Health Care

PURPOSE The short, validated, self-administered, Case-finding and Help Assessment Tool (CHAT) for lifestyle and mental health assessment of adult patients in primary health care addresses inactivity, tobacco use, alcohol and other drug misuse, problem gambling, depression, anxiety and stress, abuse, and anger problems. For each issue patients are asked whether they would like help, either during the consultation or at a later date. This study aims to assess the value of the help question.METHODS Validation of the CHAT was conducted according to the STAndards for Reporting of Diagnostic accuracy studies statement for diagnostic tests. The setting was Auckland primary care practices with populations ranging from socioeconomically advantaged to deprived. Participants were 755 consecutive primary care patients who completed the CHAT plus the help question and reference standards. Sensitivity, specificity, and likelihood ratios with and without the addition of help the question were calculated.RESULTS Sensitivity ranged from 80% to 98% for the more-common conditions (depression, nicotine dependency, anxiety, problematic drinking). For each condition, specificity increased with the addition of the help question: depression increased from 73% to 98%; anxiety 77% to 99%; drinking 85% to 99%; verbal anger 92% to 99%; verbal abuse 97% to 99%; problematic drinking and gambling 98% to 99%.CONCLUSIONS The help question increased specificity without compromising sensitivity and reduced false positives, thereby increasing the positive predictive value. It allowed patients with comorbidities to prioritize issues they wished to address, indicate their readiness to change, promote self-determination, and give the clinician an indication of which topics to pursue.