OBJECTIVE: To evaluate the level of evidence published in infertility journals with the highest impact factors. DESIGN: Systematic review. We searched in PubMed identifying potential systematic reviews with meta-analysis (SRs) and randomized controlled trials (RCTs) between 2006 and 2010 in the five fertility journals with highest impact factor. SETTING: Academic institution. PATIENT(S): None. INTERVENTION(S): None. MAIN OUTCOMES MEASURE(S): Number and proportion of potential SRs and RCTs published in 2006-2011, and quality assessment of real RCTs published in 2010. RESULT(S): Among evaluated articles, 1.5% and 6.8% were SRs and RCTs. Fertility and Sterility has been the journal with more potential SRs and RCTs, and Human Reproduction Update was the only one with an increasing trend in the number of potential SRs (from 5.3% in 2006 to 24.4% in 2011). Among confirmed RCTs, for each quality assessment item, between 50% and 85% were classified as having low risk of bias, and the most common high risk of bias was related to allocation concealment. Only 23% had a trial registration, which were associated with higher quality assessment classifications. Only 10% of RCTs reported pharmaceutical industry funding. CONCLUSION(S): This is the first study assessing the methodologic quality of publications in the top five fertility journals. More than 90% of all the publications were neither SRs nor RCTs. It is remarkable that the risk of bias was generally low. Enhancing trial registration and funding source statements represent opportunities to improve the quality of reporting. We hope this information is useful to researchers, editorial boards, and clinicians moving forward with research in our field.
OBJECTIVE: To evaluate the level of evidence published in infertility journals with the highest impact factors. DESIGN: Systematic review. We searched in PubMed identifying potential systematic reviews with meta-analysis (SRs) and randomized controlled trials (RCTs) between 2006 and 2010 in the five fertility journals with highest impact factor. SETTING: Academic institution. PATIENT(S): None. INTERVENTION(S): None. MAIN OUTCOMES MEASURE(S): Number and proportion of potential SRs and RCTs published in 2006-2011, and quality assessment of real RCTs published in 2010. RESULT(S): Among evaluated articles, 1.5% and 6.8% were SRs and RCTs. Fertility and Sterility has been the journal with more potential SRs and RCTs, and Human Reproduction Update was the only one with an increasing trend in the number of potential SRs (from 5.3% in 2006 to 24.4% in 2011). Among confirmed RCTs, for each quality assessment item, between 50% and 85% were classified as having low risk of bias, and the most common high risk of bias was related to allocation concealment. Only 23% had a trial registration, which were associated with higher quality assessment classifications. Only 10% of RCTs reported pharmaceutical industry funding. CONCLUSION(S): This is the first study assessing the methodologic quality of publications in the top five fertility journals. More than 90% of all the publications were neither SRs nor RCTs. It is remarkable that the risk of bias was generally low. Enhancing trial registration and funding source statements represent opportunities to improve the quality of reporting. We hope this information is useful to researchers, editorial boards, and clinicians moving forward with research in our field.