Can respondents accurately self-report posttraumatic growth when coached through the required cognitive steps?

Background: Coyne and Tennen [(2010). Positive psychology in cancer care: Bad science, exaggerated claims, and unproven medicine. Annals of Behavioral Medicine, 39(1), 16-26. https://doi.org/10.1007/s12160-009-9154-z] argue that completing self-reports of posttraumatic growth (PTG) requires four complicated cognitive steps. Design: We conducted two experiments designed to (1) use mental chronometry (i.e., reaction times on cognitive tasks) to test whether respondents engage in multiple cognitive steps when completing self-reports of PTG, and (2) determine whether coaching participants to take these steps results in a more valid assessment. Method: In Experiment 1, 310 undergraduates were randomly assigned to complete either the Posttraumatic Growth Inventory (PTGI) or Stress-Related Growth Scale (SRGS), and its corresponding current version that requires only one cognitive step. In Experiment 2, 306 undergraduates were randomly assigned to complete either a guided-steps version of the SRGS or the original SRGS. Results: Experiment 1 indicated a very small difference in completion time for the PTGI, but not the SRGS, in comparison to the current versions, suggesting respondents do not engage in the four required cognitive steps. In Experiment 2, participants reported less PTG when coached to go through the four cognitive steps, but the resulting scores were generally unrelated to measures of convergent and predictive validity. Conclusion: We conclude that individuals cannot accurately report PTG, even when explicitly coached.