Abstract
Aim
Type D personality, a joint tendency toward negative affectivity (NA) and social inhibition (SI), has been linked to various medical and psychosocial outcomes. The recent failure to replicate earlier findings could result from the various methods used to assess the Type D effect. Despite recommendations to analyze the continuous NA and SI scores, a popular approach groups people as having Type D personality or not. This dichotomous method cannot distinguish a Type D effect from situations where only NA or SI is causally related to the outcome, suggesting the literature contains studies that falsely conclude that having high scores on both traits is causally important. Here, we systematically assess the extent of this problem.
Methods
We conducted a systematic review including all studies that estimated a Type D effect on any outcome according to both the continuous and dichotomous method.
Results
158 previously published analyses were included in our review. In 89 of those analyses a Type D effect was concluded based on the dichotomous method. Of those 89 analyses, only 37 (41.6%) were a Type D effect based on the continuous method, while 42 (47.2%) were main effects of NA or SI only.
Conclusion
Half of the published Type D effects according to the dichotomous method may more likely be effects of NA or SI only. Earlier published studies using the dichotomous method should be reanalyzed using the continuous method to determine whether it is really Type D or merely NA or SI that is driving the outcome.
Type D personality, a joint tendency toward negative affectivity (NA) and social inhibition (SI), has been linked to various medical and psychosocial outcomes. The recent failure to replicate earlier findings could result from the various methods used to assess the Type D effect. Despite recommendations to analyze the continuous NA and SI scores, a popular approach groups people as having Type D personality or not. This dichotomous method cannot distinguish a Type D effect from situations where only NA or SI is causally related to the outcome, suggesting the literature contains studies that falsely conclude that having high scores on both traits is causally important. Here, we systematically assess the extent of this problem.
Methods
We conducted a systematic review including all studies that estimated a Type D effect on any outcome according to both the continuous and dichotomous method.
Results
158 previously published analyses were included in our review. In 89 of those analyses a Type D effect was concluded based on the dichotomous method. Of those 89 analyses, only 37 (41.6%) were a Type D effect based on the continuous method, while 42 (47.2%) were main effects of NA or SI only.
Conclusion
Half of the published Type D effects according to the dichotomous method may more likely be effects of NA or SI only. Earlier published studies using the dichotomous method should be reanalyzed using the continuous method to determine whether it is really Type D or merely NA or SI that is driving the outcome.
| Original language | English |
|---|---|
| Pages (from-to) | 19-19 |
| Number of pages | 1 |
| Journal | Journal of Psychosomatic Research |
| Volume | 169 |
| DOIs | |
| Publication status | Published - 2023 |