Creative productivity, age, and stress: a biographical time-series analysis of 10 classical composers.

The determinants of creative productivity were specified in the form of six hypotheses. Using a multivariate cross-sectional time-series design with several controls, the lives and works of 10 classical composers were analyzed into consecutive 5-year age periods. Two independent measures of productivity were operationalized (works and themes), with each measure subdivided into major and minor compositions according to a citation criterion. It was consistently found across both productivity measures that (a) quality of productivity is a probabilistic consequence of productive quantity and (b) total productivity, while affected by age and physical illness, is otherwise free of external influences (viz., social reinforcement, biographical stress, war intensity, and internal disturbances). Due to the more selective nature of the thematic productivity measure, the criterion of total themes alone was affected by competition and a time-wise bias. The article closes with a brief discussion of the broad substantive utility of the methodological design.