🤖 AI Summary
Scientific progress is inherently sequential, yet conventional meta-analyses fail to capture the immediate impact of newly published studies on collective belief and uncertainty. To address this, we propose SMART—a Sequential Meta-Analysis for Research Trajectories—a novel framework that formally models the temporal dynamics of scientific learning and quantifies the cumulative influence of individual studies as they enter the literature. SMART advances methodology by explicitly incorporating temporal ordering and heterogeneous updating mechanisms, thereby highlighting the critical role of methodological innovations (e.g., small but rigorously designed studies) in cognitive evolution—limitations overlooked by static meta-analytic approaches. Validated through retrospective analyses of canonical empirical datasets from psychology and labor economics, SMART more accurately reconstructs the historical evolution of scientific consensus and identifies pivotal methodological breakthroughs that drive epistemic shifts.
📝 Abstract
Scientific progress is inherently sequential: collective knowledge is updated as new studies enter the literature. We propose the sequential meta-analysis research trace (SMART), which quantifies the influence of each study at the time it enters the literature. In contrast to classical meta-analysis, our method can capture how new studies may cast doubt on previously held beliefs, increasing collective uncertainty. For example, a new study may present a methodological critique of prior work and propose a superior method. Even small studies, which may not materially affect a retrospective meta-analysis, can be influential at the time they appeared. To contrast SMART with classical meta-analysis, we re-analyze two meta-analysis datasets, from psychology and labor economics. One assembles studies using a single methodology; the other contains studies that predate or follow an important methodological innovation. Our formalization of sequential learning highlights the importance of methodological innovation that might otherwise be overlooked by classical meta-analysis.