Assessment of the Quality of Reporting in Abstracts of Randomized Controlled Trials Published in Five Leading Chinese Medical Journals

Background

Clear, transparent and sufficiently detailed abstracts of randomized trials (RCTs), published in journal articles are important because readers will often base their initial assessment of a trial on such information. However, little is known about the quality of reporting in abstracts of RCTs published in medical journals in China.

Methods

We identified RCTs abstracts from 5 five leading Chinese medical journals published between 1998 and 2007 and indexed in MEDLINE. We assessed the quality of reporting of these abstracts based on the Consolidated Standards of Reporting Trials (CONSORT) abstract checklist. We also sought to identify whether any differences exist in reporting between the Chinese and English language version of the same abstract.

Results

We identified 332 RCT abstracts eligible for examination. Overall, the abstracts we examined reported 0–8 items as designated in the CONSORT checklist. On average, three items were reported per abstract. Details of the interventions (288/332; 87%), the number of participants randomized (216/332; 65%) and study objectives (109/332; 33%) were the top three items reported. Only two RCT abstracts reported details of trial registration, no abstracts reported the method of allocation concealment and only one mentioned specifically who was blinded. In terms of the proportion of RCT abstracts fulfilling a criterion, the absolute difference (percentage points) between the Chinese and English abstracts was 10% (ranging from 0 to 25%) on average, per item.

Conclusions

The quality of reporting in abstracts of RCTs published in Chinese medical journals needs to be improved. We hope that the introduction and endorsement of the CONSORT for Abstracts guidelines by journals reporting RCTs will lead to improvements in the quality of reporting.     

Assessment of the Quality of Reporting of Randomised Controlled Trials in Otorhinolaryngologic Literature – Adherence to the CONSORT Statement

Background

Randomised Controlled Trials (RCTs) are the preferred study design when comparing therapeutical interventions in medicine. To improve clarity, consistency and transparency of reporting RCTs, the Consolidated Standards of Reporting Trials (CONSORT) statement was developed.

Objectives

(1) To assess the quality of reports and abstracts of RCTs in otorhinolaryngologic literature by using CONSORT checklists, (2) to compare the quality of reports and abstracts of otorhinolaryngologic RCTs between the top 5 general medical journals and top 5 otorhinolaryngologic journals, and (3) to formulate recommendations for authors and editors of otorhinolaryngologic (‘ENT’) journals.

Methods

Based on 2012 ISI Web of Knowledge impact factors, the top 5 general medical and ENT journals were selected. On 25 June 2014, using a highly sensitive Cochrane RCT filter and ENT filter, possibly relevant articles since January 1st, 2010 were retrieved and relevant RCTs were selected. We assessed how many CONSORT items were reported adequately in reports and abstracts and compared the two journal types.

Results

Otorhinolaryngologic RCTs (n = 15) published in general medical journals reported a mean of 92.1% (95% confidence interval: 89.5%–94.7%) of CONSORT items adequately, whereas RCTs (n = 18) published in ENT journals reported a mean of 71.8% (66.7%–76.8%) adequately (p < 0.001). For abstracts, means of 70.0% (63.7%–76.3%) and 32.3% (26.6–38.0%) were found respectively (p < 0.001). Large differences for specific items exist between the two journal types.

Conclusion

The quality of reporting of RCTs in otorhinolaryngologic journals is suboptimal. RCTs published in general medical journals have a higher quality of reporting than RCTs published in ENT journals. We recommend authors to report their trial according to the CONSORT Statement and advise editors to endorse the CONSORT Statement and implement the CONSORT Statement in the editorial process to ensure more adequate reporting of RCTs and their abstracts.     

The methodological quality of 176,620 randomized controlled trials published between 1966 and 2018 reveals a positive trend but also an urgent need for improvement

Many randomized controlled trials (RCTs) are biased and difficult to reproduce due to methodological flaws and poor reporting. There is increasing attention for responsible research practices and implementation of reporting guidelines, but whether these efforts have improved the methodological quality of RCTs (e.g., lower risk of bias) is unknown. We, therefore, mapped risk-of-bias trends over time in RCT publications in relation to journal and author characteristics. Meta-information of 176,620 RCTs published between 1966 and 2018 was extracted. The risk-of-bias probability (random sequence generation, allocation concealment, blinding of patients/personnel, and blinding of outcome assessment) was assessed using a risk-of-bias machine learning tool. This tool was simultaneously validated using 63,327 human risk-of-bias assessments obtained from 17,394 RCTs evaluated in the Cochrane Database of Systematic Reviews (CDSR). Moreover, RCT registration and CONSORT Statement reporting were assessed using automated searches. Publication characteristics included the number of authors, journal impact factor (JIF), and medical discipline. The annual number of published RCTs substantially increased over 4 decades, accompanied by increases in authors (5.2 to 7.8) and institutions (2.9 to 4.8). The risk of bias remained present in most RCTs but decreased over time for allocation concealment (63% to 51%), random sequence generation (57% to 36%), and blinding of outcome assessment (58% to 52%). Trial registration (37% to 47%) and the use of the CONSORT Statement (1% to 20%) also rapidly increased. In journals with a higher impact factor (>10), the risk of bias was consistently lower with higher levels of RCT registration and the use of the CONSORT Statement. Automated risk-of-bias predictions had accuracies above 70% for allocation concealment (70.7%), random sequence generation (72.1%), and blinding of patients/personnel (79.8%), but not for blinding of outcome assessment (62.7%). In conclusion, the likelihood of bias in RCTs has generally decreased over the last decades. This optimistic trend may be driven by increased knowledge augmented by mandatory trial registration and more stringent reporting guidelines and journal requirements. Nevertheless, relatively high probabilities of bias remain, particularly in journals with lower impact factors. This emphasizes that further improvement of RCT registration, conduct, and reporting is still urgently needed.

Many randomized controlled trials (RCTs) are biased and difficult to reproduce due to methodological flaws and poor reporting. Analysis of 176,620 RCTs published between 1966 and 2018 reveals that the risk of bias in RCTs generally decreased. Nevertheless, relatively high probabilities of bias remain, showing that further improvement of RCT registration, conduct, and reporting is still urgently needed.     

Ultrasound enhanced prehospital thrombolysis using microbubbles infusion in patients with acute ST elevation myocardial infarction: Rationale and design of the Sonolysis study

Background

The CONSORT Statement provides recommendations for reporting randomized controlled trials. We assessed the extent to which leading medical journals that publish reports of randomized trials incorporate the CONSORT recommendations into their journal and editorial processes.

Methods

This article reports on two observational studies. Study 1: We examined the online version of 'Instructions to Authors' for 165 high impact factor medical journals and extracted all text mentioning the CONSORT Statement or CONSORT extension papers. Any mention of the International Committee of Medical Journal Editors (ICMJE) or clinical trial registration were also sought and extracted. Study 2: We surveyed the editor-in-chief, or editorial office, for each of the 165 journals about their journal's endorsement of CONSORT recommendations and its incorporation into their editorial and peer-review processes.

Results

Study 1: Thirty-eight percent (62/165) of journals mentioned the CONSORT Statement in their online 'Instructions to Authors'; of these 37% (23/62) stated this was a requirement, 63% (39/62) were less clear in their recommendations. Very few journals mentioned the CONSORT extension papers. Journals that referred to CONSORT were more likely to refer to ICMJE guidelines (RR 2.16; 95% CI 1.51 to 3.08) and clinical trial registration (RR 3.67; 95% CI 2.36 to 5.71) than those journals which did not. Study 2: Thirty-nine percent (64/165) of journals responded to the on-line survey, the majority were journal editors. Eighty-eight percent (50/57) of journals recommended authors comply with the CONSORT Statement; 62% (35/56) said they would require this. Forty-one percent (22/53) reported incorporating CONSORT into their peer-review process and 47% (25/53) into their editorial process. Eighty-one percent (47/58) reported including CONSORT in their 'Instructions to Authors' although there was some inconsistency when cross checking information on the journal's website. Sixty-nine percent (31/45) of journals recommended authors comply with the CONSORT extension for cluster trials, 60% (27/45) for harms and 42% (19/45) for non-inferiority and equivalence trials. Few journals mentioned these extensions in their 'Instructions to Authors'.

Conclusion

Journals should be more explicit in their recommendations and expectations of authors regarding the CONSORT Statement and related CONSORT extensions papers.     

How Psychiatry Journals Support the Unbiased Translation of Clinical Research. A Cross-Sectional Study of Editorial Policies

Introduction

Reporting guidelines (e.g. CONSORT) have been developed as tools to improve quality and reduce bias in reporting research findings. Trial registration has been recommended for countering selective publication. The International Committee of Medical Journal Editors (ICMJE) encourages the implementation of reporting guidelines and trial registration as uniform requirements (URM). For the last two decades, however, biased reporting and insufficient registration of clinical trials has been identified in several literature reviews and other investigations. No study has so far investigated the extent to which author instructions in psychiatry journals encourage following reporting guidelines and trial registration.

Method

Psychiatry Journals were identified from the 2011 Journal Citation Report. Information given in the author instructions and during the submission procedure of all journals was assessed on whether major reporting guidelines, trial registration and the ICMJE’s URM in general were mentioned and adherence recommended.

Results

We included 123 psychiatry journals (English and German language) in our analysis. A minority recommend or require 1) following the URM (21%), 2) adherence to reporting guidelines such as CONSORT, PRISMA, STROBE (23%, 7%, 4%), or 3) registration of clinical trials (34%). The subsample of the top-10 psychiatry journals (ranked by impact factor) provided much better but still improvable rates. For example, 70% of the top-10 psychiatry journals do not ask for the specific trial registration number.

Discussion

Under the assumption that better reported and better registered clinical research that does not lack substantial information will improve the understanding, credibility, and unbiased translation of clinical research findings, several stakeholders including readers (physicians, patients), authors, reviewers, and editors might benefit from improved author instructions in psychiatry journals. A first step of improvement would consist in requiring adherence to the broadly accepted reporting guidelines and to trial registration.     

Reporting quality of randomized controlled trials in patients with HIV on antiretroviral therapy: a systematic review

Background

To allow for correct evaluation of clinical trial results, readers require comprehensive, clear, and highly transparent information on the methodology used and the results obtained. This study aimed to evaluate the quality of reporting in articles on randomized controlled trials (RCTs) of antiretroviral therapy (ART) in the field of HIV/AIDS.

Methods

We searched for original articles on RCTs of ART developed in the field of HIV/AIDS in PubMed database by 5 April 2016. Searched articles were divided into three groups based on the revision year in which the Consolidated Standards of Reporting Trials (CONSORT) guidelines were published: Period 1 (1996–2001); Period 2 (2002–2010); and Period 3 (2011–2016). We evaluated the articles using the reporting rates of the 37 items in the CONSORT 2010 checklist, five items in the protocol deviation, and the three items in the ethics.

Results

Fifty-two articles were extracted and included in this study. Many of the reporting rates calculated using the CONSORT 2010 checklist showed a significantly increasing trend over the successive periods (65% in Period 1, 67% in Period 2, 79% in Period 3; p?<?0.0001). The items with reporting rates?<?50% were “the presence or absence of a protocol change and the reason for such a change,” “randomization and blinding,” and “where the full trial protocol can be accessed.” Reporting rates of deviations were as low as?<?30%, while the reporting rates for patient compliance were the highest (>80% in Period 3) among the five items. The reporting rates for obtaining informed consent and approval by the ethics committee or institutional review board were high (>88%), regardless of the time period assessed.

Conclusion

In terms of representative RCT articles in the field of HIV/AIDS, the reporting rate of the items defined by CONSORT was approximately 70%, improving over the successive CONSORT statement revision periods.

     

Individual patient data meta-analysis of acupuncture for chronic pain: protocol of the Acupuncture Trialists' Collaboration

Objectives

To evaluate the use and reporting of adjusted analysis in randomised controlled trials (RCTs) and compare the quality of reporting before and after the revision of the CONSORT Statement in 2001.

Design

Comparison of two cross sectional samples of published articles.

Data Sources

Journal articles indexed on PubMed in December 2000 and December 2006.

Study Selection

Parallel group RCTs with a full publication carried out in humans and published in English

Main outcome measures

Proportion of articles reported adjusted analysis; use of adjusted analysis; the reason for adjustment; the method of adjustment and the reporting of adjusted analysis results in the main text and abstract.

Results

In both cohorts, 25% of studies reported adjusted analysis (84/355 in 2000 vs 113/422 in 2006). Compared with articles reporting only unadjusted analyses, articles that reported adjusted analyses were more likely to specify primary outcomes, involve multiple centers, perform stratified randomization, be published in general medical journals, and recruit larger sample sizes. In both years a minority of articles explained why and how covariates were selected for adjustment (20% to 30%). Almost all articles specified the statistical methods used for adjustment (99% in 2000 vs 100% in 2006) but only 5% and 10%, respectively, reported both adjusted and unadjusted results as recommended in the CONSORT guidelines.

Conclusion

There was no evidence of change in the reporting of adjusted analysis results five years after the revision of the CONSORT Statement and only a few articles adhered fully to the CONSORT recommendations.     

The quality of reporting of RCTs used within a postoperative pain management meta-analysis, using the CONSORT statement

Background

Randomized controlled trials (RCTs) are routinely used in systematic reviews and meta-analyses that help inform healthcare and policy decision making. The proper reporting of RCTs is important because it acts as a proxy for health care providers and researchers to appraise the quality of the methodology, conduct and analysis of an RCT. The aims of this study are to analyse the overall quality of reporting in 23 RCTs that were used in a meta-analysis by assessing 3 key methodological items, and to determine factors associated with high quality of reporting. It is hypothesized that studies with larger sample sizes, that have funding reported, that are published in journals with a higher impact factor and that are in journals that have adopted or endorsed the CONSORT statement will be associated with better overall quality of reporting and reporting of key methodological items.

Methods

We systematically reviewed RCTs used within an anesthesiology related post-operative pain management meta-analysis. We included all of the 23 RCTs used, all of which were parallel design that addressed the use of femoral nerve block in improving outcomes after total knee arthroplasty. Data abstraction was done independently by two reviewers. The two main outcomes were: 1) 15 point overall quality of reporting score (OQRS) based on the Consolidated Standards for Reporting Trials (CONSORT) and 2) 3 point key methodological item score (KMIS) based on allocation concealment, blinding and intention-to-treat analysis.

Results

Twenty-three RCTs were included. The median OQRS was 9.0 (Interquartile Range?=?3). A multivariable regression analysis did not show any significant association between OQRS or KMIS and our four predictor variables hypothesized to improve reporting. The direction and magnitude of our results when compared to similar studies suggest that the sample size and impact factor are associated with improved key methodological item reporting.

Conclusions

The quality of reporting of RCTs used within an anesthesia related meta-analysis is poor to moderate. The information gained from this study should be used by journals to register the urgency for RCTs to be clear and transparent in reporting to help make literature accessible and comparable.     

CONSORT Item Reporting Quality in the Top Ten Ranked Journals of Critical Care Medicine in 2011: A Retrospective Analysis

IntroductionReporting randomised controlled trials is a key element in order to disseminate research findings. The CONSORT statement was introduced to improve the reporting quality. We assessed the adherence to the CONSORT statement of randomised controlled trials published 2011 in the top ten ranked journals of critical care medicine (ISI Web of Knowledge 2011, Thomson Reuters, London UK).MethodsDesign. We performed a retrospective cross sectional data analysis. Setting. This study was executed at the University Hospital of RWTH, Aachen. Participants. We selected the following top ten listed journals according to ISI Web of Knowledge (Thomson Reuters, London, UK) critical care medicine ranking in the year 2011: American Journal of Respiratory and Critical Care Medicine, Critical Care Medicine, Intensive Care Medicine, CHEST, Critical Care, Journal of Neurotrauma, Resuscitation, Pediatric Critical Care Medicine, Shock and Minerva Anestesiologica. Main outcome measures. We screened the online table of contents of each included journal, to identify the randomised controlled trials. The adherence to the items of the CONSORT Checklist in each trial was evaluated. Additionally we correlated the citation frequency of the articles and the impact factor of the respective journal with the amount of reported items per trial.ResultsWe analysed 119 randomised controlled trials and found, 15 years after the implementation of the CONSORT statement, that a median of 61,1% of the checklist-items were reported. Only 55.5% of the articles were identified as randomised trials in their titles. The citation frequency of the trials correlated significantly (rs = 0,433; p<0,001 and r = 0,331; p<0,001) to the CONSORT statement adherence. The impact factor showed also a significant correlation to the CONSORT adherence (r = 0,386; p<0,001).ConclusionThe reporting quality of randomised controlled trials in the field of critical care medicine remains poor and needs considerable improvement.     

Assessing the quality of reports about randomized controlled trials of acupuncture treatment on mild cognitive impairment

Objective

To evaluate the reports'' qualities which are about randomized controlled trials (RCTs) of acupuncture treatment on Mild Cognitive Impairment (MIC).

Methods

Nine databases including the Cochrane Central Register of Controlled Trials (CENTRAL,2010), PUBMED (1984-5/2010), EMbase (1984-5/2010), MEDLINE (1984-5/2010), CINAL (1984-5/2010), China National Knowledge Infrastructure (CNKI, 1980-5/2010), China Biomedicine Database disc (CBMdisc, 1980-5/2010), VIP (a full text issues database of China, 1989-5/2010) were searched systematically. Hand search for further references was conducted. Language was limited to Chinese and English. We identified 14 RCTs that used acupuncture as an intervention and assessed the quality of these reports against the Consolidated Standards for Reporting of Trials (CONSORT) statement and Standards for Reporting Interventions in Controlled Trials of Acupuncture (STRICTA).

Results

In regard to the items in the CONSORT statement, 13(92.86%) RCTs described baseline demographic and clinical characteristics in each group. 7 (50.0%) mentioned the method of generating the random sequence, only 2 (14.3%) RCTs had adequate allocation concealment. No RCTs used blinding. RCTs reported the sample size calculation. In regard to the items in STRICTA, 10 (71.43%) mentioned the depths of insertion, 6 (42.86%) reported acupuncture response, 11 (78.57%) mentioned the technique of acupuncture, 12 (85.71%) recorded the time, and only 3 (21.43%) RCTs reported the numbers of needles inserted. No RCTs reported the background of the acupuncture practitioners and professional title of practitioners.

Conclusion

The reporting quality of RCTs of acupuncture for mild cognitive impairment was moderate to low. The CONSORT statement and STRICTA should be used to standardize the reporting of RCTs of acupuncture in future.     

Assessment of the Reporting Quality of Randomized Controlled Trials on the Treatment of Diabetes Mellitus with Traditional Chinese Medicine: A Systematic Review

Background

After the publication of the CONSORT 2010 statement, few studies have been conducted to assess the reporting quality of randomized clinical trials (RCTs) on treatment of diabetes mellitus with Traditional Chinese Medicine (TCM) published in Chinese journals.

Objective

To investigate the current situation of the reporting quality of RCTs in leading medical journals in China with the CONSORT 2010 statement as criteria.

Methods

The China National Knowledge Infrastructure (CNKI) electronic database was searched for RCTs on the treatment of diabetes mellitus with TCM published in the Journal of Traditional Chinese Medicine, Chinese Journal of Integrated Traditional & Western Medicine, and the China Journal of Chinese Materia Medica from January to December 2011. We excluded trials reported as “animal studies”, “in vitro studies”, “case studies”, or “systematic reviews”. The CONSORT checklist was applied by two independent raters to evaluate the reporting quality of all eligible trials after discussing and comprehending the items thoroughly. Each item in the checklist was graded as either “yes” or “no” depending on whether it had been reported by the authors.

Results

We identified 27 RCTs. According to the 37 items in the CONSORT checklist, the average reporting percentage was 45.0%, in which the average reporting percentage for the “title and abstract”, the “introduction”, the “methods”, the “results”, the “discussion” and the “other information” was 33.3%, 88.9%, 36.4%, 54.4%, 71.6% and 14.8%, respectively. In the Journal of Traditional Chinese Medicine, Chinese Journal of Integrated Traditional & Western Medicine, and the China Journal of Chinese Materia Medica the average reporting percentage was 42.2%, 56.8%, and 46.0%, respectively.

Conclusions

The reporting quality of RCTs in these three journals was insufficient to allow readers to assess the validity of the trials. We recommend that editors require authors to use the CONSORT statement when reporting their trial results as a condition of publication.     

Quality and content of abstracts in papers reporting about drug exposures during pregnancy

BACKGROUND: Most clinicians read only the abstract of papers in scientific journals. Therefore, it is very important that abstracts contain as much information as possible, to summarize the data succinctly. Our objectives were to evaluate the quality of information in abstracts reporting human fetal outcomes following drug exposure during pregnancy. METHODS: We developed quality criteria based on previous work, modifying them for use with pregnancy outcomes. Quality scores were calculated as present/absent for all of the equally weighted criteria, then expressed as percentages (present/[present + absent]). We examined a random sample of 100 abstracts obtained through searches of MEDLINE, EMBASE, and the Web of Science databases from 1990 to 2005. Average quality scores were compared across designs (cohort, case-control, meta-analysis, and mixed design) Using Kruskal-Wallis ANOVA and structured/unstructured formats using Student's t test. RESULTS: The overall average quality was 59.2% +/- 14% (median, 61.5%; range, 15.4-83.3%). Quality was not significantly different across designs (P = .16) or between structured and unstructured abstracts (P = .44). Quality scores increased over time (Rho = 0.23, P = .02). Most frequently absent were baseline risk (94%), drug dose (91%), nonsignificant P values (72%), confounders (69%), significant P values (57%), and risk difference (48%). CONCLUSIONS: Abstracts provide insufficient information, particularly baseline risk values, for readers to make evidence-based decisions regarding drug use during pregnancy. Efforts need to be made to improve the quality of abstracts and include critical information such as baseline risk.     

Use of Kampo Diagnosis in Randomized Controlled Trials of Kampo Products in Japan: A Systematic Review

Background

The Committee for Evidence-based Medicine (EBM) of the Japan Society for Oriental Medicine started compiling Evidence Reports of Kampo Treatment (EKAT) in 2007. EKAT is a compilation of structured abstracts of randomized controlled trials (RCTs), along with comments by a third party reviewer. As of 31 December, 2012, there were 378 RCTs of Kampo medicines in Japan. The primary research question of this study is “How frequently is Kampo diagnosis used in RCTs of Kampo medicines?” The secondary research question is “When is Kampo diagnosis used in RCTs?”

Materials and Methods

The structured abstract (SA) of each RCT article was reviewed to examine how Kampo diagnosis was used in RCTs, especially how Kampo diagnosis was used in the randomization process.

Results

Kampo diagnosis was used before randomization in 27 RCTs (7.1%), after randomization in 31 RCTs (8.2%), and not used in 320 RCTs (84.7%). Before randomization, Kampo diagnosis was used as a criterion for inclusion in 10 RCTs, criterion for exclusion in 9 RCTs, and criteria for both inclusion and exclusion in 2 RCTs. Kampo formulas were determined according to Kampo diagnosis in 7 RCTs. After randomization, subgroup analyses according to Kampo diagnosis were done in 27 RCTs, and grade of disease severity at Kampo diagnosis was used for analysis as an endpoint in 4 RCTs.

Conclusions

Kampo diagnosis was used before randomization only in approximately 15% of RCTs, and the number of RCT articles using Kampo diagnosis after randomization was almost the same as that before randomization. Further studies to determine the good RCTs conforming to CONSORT requirements and good systematic reviews conforming to PRISMA requirements are needed to clarify the significance of Kampo diagnosis.     

Systematic Review and Meta-Analysis of Validation Studies on a Diabetes Case Definition from Health Administrative Records

Objectives

Health administrative data are frequently used for diabetes surveillance. We aimed to determine the sensitivity and specificity of a commonly-used diabetes case definition (two physician claims or one hospital discharge abstract record within a two-year period) and their potential effect on prevalence estimation.

Methods

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched Medline (from 1950) and Embase (from 1980) databases for validation studies through August 2012 (keywords: “diabetes mellitus”; “administrative databases”; “validation studies”). Reviewers abstracted data with standardized forms and assessed quality using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. A generalized linear model approach to random-effects bivariate regression meta-analysis was used to pool sensitivity and specificity estimates. We applied correction factors derived from pooled sensitivity and specificity estimates to prevalence estimates from national surveillance reports and projected prevalence estimates over 10 years (to 2018).

Results

The search strategy identified 1423 abstracts among which 11 studies were deemed relevant and reviewed; 6 of these reported sensitivity and specificity allowing pooling in a meta-analysis. Compared to surveys or medical records, sensitivity was 82.3% (95%CI 75.8, 87.4) and specificity was 97.9% (95%CI 96.5, 98.8). The diabetes case definition underestimated prevalence when it was ≤10.6% and overestimated prevalence otherwise.

Conclusion

The diabetes case definition examined misses up to one fifth of diabetes cases and wrongly identifies diabetes in approximately 2% of the population. This may be sufficiently sensitive and specific for surveillance purposes, in particular monitoring prevalence trends. Applying correction factors to adjust prevalence estimates from this definition may be helpful to increase accuracy of estimates.