Datasets and codebook for: A cross-sectional study of the completeness of preregistrations by psychological authors from German-speaking institutions

Preregistering confirmatory research aims at reducing researchers’ degrees of freedom and increasing transparency to ultimately increase replicability. Yet, the extent to which preregistrations actually achieve these goals depends on the completeness of a preregistration. To scrutinize the completeness of current preregistrations, we coded all preregistrations mentioned in journal articles published by psychologists from institutions in German-speaking countries in 2020 as to whether they contain six procedural specifications: (1) the hypothesized pattern of results, (2) the measures, (3) planned sample size, (4) exclusion criteria, (5) planned analyses to test the hypotheses, and (6) a timestamp. In addition, we consider transparency related elements. Our results show that the completeness of preregistration was neither associated with the journal’s Impact Factor nor its Transparency and Openness Promotion Factor. Approximately, half of the preregistrations contained all six procedural specifications. Hence, in line with previous research, our findings indicate that when considering publications from diverse subdisciplines of psychology, there was room for improvement regarding the completeness of preregistrations in psychology. We discuss steps to improve preregistration completeness.