Accurate and consistent reviews of documents describing research studies are essential to valid and generalizable inferences in a meta-analysis. Traditionally a small number of reviewers screen studies using the title, abstract, and possibly the full text to determine a study's eligibility for a meta-analysis. This study explores whether reviewing loads and resources to support accurate and consistent reviewing have increased over time. A survey of N = 193 meta-analyses published between 1980-2019 showed that the average number of documents reviewed has increased, especially since 2010, but the typical number of reviewers has not changed over the past 40 years. The importance of meta-analysts providing information about reviewers and the review process to help readers evaluate the validity and generalizability of inferences is emphasized. This information would typically include the number of reviewers and their qualifications, number of titles, abstracts, and full-text documents reviewed, time spent reviewing documents, evidence of the accuracy and consistency of reviews, and the role of software in facilitating reviewing.