meta-analysis of Hersey and Blanchard's Situational Leadership Theory

This study examined the validity of Hersey and Blanchard' s Situational Leadership Theory (SLT). The meta-analytic techniques of Hunter, Schmidt, and Jackson were used to investigate two research questions: (1) Does the matching of leadership styles and follower maturity influence outcome measures? (2) Can any of the remaining variance be attributed to moderator variables? A literature search from January, 1968 to April, 1990 produced 26 acceptable studies with 52 separate effects. A correlation coefficient was reported for each study. In studies with multiple effects the correlation was computed from an aggregation of those effects. A mean and variance were tabulated, and corrections were made for sampling error and attenuation. The corrected mean was.0498 with a variance of.0076. This was not significant. The criterion for significance was that the mean must be more than two standard deviations greater than zero (Hunter, Schmidt, & Jackson, 1982, p.28). An analysis of residual variance justified a search for moderator effects. Length of study proved to be the only influential moderator (.4343 mean and 0.0 standard deviation) when the Vertiz, et al. outlier was removed. With the exception of increasing the length of treatment, no evidence was obtained to support the Situational Leadership Theory. Future research should include longer durations, and more designs should incorporate outcome measures. Finally, measurement precision needs to improve for both leadership and maturity.