OBJECTIVE: To develop a short instrument to measure determinants of innovations that may affect its implementation. DESIGN: We pooled the original data from eight empirical studies of the implementation of evidence-based innovations. The studies used a list of 60 potentially relevant determinants based on a systematic review of empirical studies and a Delphi study among implementation experts. Each study used similar methods to measure both the implementation of the innovation and determinants. Missing values in the final data set were replaced by plausible values using multiple imputation. We assessed which determinants predicted completeness of use of the innovation (% of recommendations applied). In addition, 22 implementation experts were consulted about the results and about implications for designing a short instrument. SETTING: Eight innovations introduced in Preventive Child Health Care or schools in the Netherlands. PARTICIPANTS: Doctors, nurses, doctor's assistants and teachers; 1977 respondents in total. RESULTS: The initial list of 60 determinants could be reduced to 29. Twenty-one determinants were based on the pooled analysis of the eight studies, seven on the theoretical expectations of the experts consulted and one new determinant was added on the basis of the experts' practical experience. CONCLUSIONS: The instrument is promising and should be further validated. We invite researchers to use and explore the instrument in multiple settings. The instrument describes how each determinant should preferably be measured (questions and response scales). It can be used both before and after the introduction of an innovation to gain an understanding of the critical change objectives.