Background The quality of systematic reviews and meta-analyses (SR/MAs) depends on the extent of the methods used. We investigated the methodological steps used by authors of SR/MAs of clinical trials via an author survey. Methods We conducted an email-based cross-sectional study by contacting corresponding authors of SR/MAs that were published in 2015 and 2016 and retrieved through the PubMed database. The 27-item questionnaire was developed to study the methodological steps used by authors when conducting a SR/MA and the demographic characteristics of the respondent. Besides the demographic characteristics, methodological questions regarding the source, extraction and synthesis of data were included. Results From 10,292 emails sent, 384 authors responded and were included in the final analysis. Manual searches were carried out by 69.2% of authors, while 87.3% do updated searches, 49.2% search grey literature, 74.9% use the Cochrane tool for risk of bias assessment, 69.8% assign more than two reviewers for data extraction, 20.5% use digital software to extract data from graphs, 57.9% use raw data in the meta-analysis, and 43.8% meta-analyze both adjusted and non-adjusted data. There was a positive correlation of years of experience in conducting of SR/MAs with both searching grey literature ( P = 0.0003) and use of adjusted and non-adjusted data ( P = 0.006). Conclusions Many authors still do not carry out many of the vital methodological steps to be taken when performing any SR/MA. The experience of the authors in SR/MAs is highly correlated with use of the recommended tips for SR/MA conduct. The optimal methodological approach for researchers conducting a SR/MA should be standardized. Electronic supplementary material The online version of this article (10.1186/s12874-019-0780-2) contains supplementary material, which is available to authorized users.

Background: Chronic pleural empyema (CPE) is the last phase of the triphasic process of pleural empyema development. Lung decortication is the corner stone in management of chronic empyema. This study aimed to objectively evaluate the efficacy of conventional decortication operation in chronic pleural empyema in adult patients. Also to prove that decortication of variable sizes of chronic empyema thoracis lesions is followed by improvement considering respiratory impairment. Methods: This prospective clinical study was conducted on 103 patients undergoing elective lung decortication operation for management of chronic empyema. All patients were subjected to the history taking, general examination, chest examination, computed tomography (CT), pulmonary function test and arterial blood gases. Postoperative evaluation was done in outpatient clinic 6 months post operatively including: Full clinical examination, investigations (acute phase reactants, CT chest, PFT and arterial blood gases. Results: Total leucocytic count, ESR 1st hour, ESR 2nd hour and CRP were significantly decreased in post than pre. FEV1 and FVC were significantly increased in post than pre (P <0.001). FEV1 / FVC Ratio was significantly decreased in post than pre (P <0.001). Transverse and antero-posterior diameters of affected hemithorax were significantly increased in post than pre (P <0.001, 0.019 respectively). Transverse and antero-posterior diameters of normal hemithorax were insignificantly different between post and pre. PaO2 and SpO2 were significantly increased in post than pre (P <0.001). PaCO2 was significantly decreased in post than pre (P <0.001). Conclusions: The improvement in the lung function, arterial blood gases, transverse and antero-posterior diameter of affected and normal hemithorax was proposed to have resulted from the decortication in chronic empyema thoracis. Decortication of variable sizes of chronic pleural empyema lesions is followed by objective improvement considering respiratory impairment.