EV-0047
Wanting to change is not nothing - but only one method worked
Hudson, N. W., & Fraley, R. C. (2015). Journal of Personality and Social Psychology, 109(3), 490-507 · Source
What this entitles us to say
Two 16-week randomized longitudinal experiments finding that people who wanted to increase on a trait did measurably increase on it - in self-reports and in trait-relevant daily behavior - and that of two interventions tested, only the one training implementation intentions actually helped.
What it found
Two 16-week intensive longitudinal randomized experiments. People who expressed goals to increase on any Big Five trait at the start did experience actual increases in their self-reports of that trait and in trait-relevant daily behavior over the following sixteen weeks.
Two interventions were tested. One was ineffective. The one that trained participants to generate implementation intentions - specific if-then plans - catalysed their ability to achieve the change.
Why it matters here
A16 has to answer how, not just whether. This is the entry that names the mechanism, and it names it by elimination: two methods were tried, one failed, and the difference between them is what the module should teach.
Three things follow directly into the design.
Volition is the entry condition. People changed in the direction they wanted to change. That is an argument for the whole diagnose-then-choose structure: the assessment's job is partly to produce a genuine want, not merely a score. A trait a leader has not chosen to work on is unlikely to move.
Good intentions are not a method. One of the two interventions did nothing. The program should assume that encouragement, reflection and awareness on their own belong in the failed condition until shown otherwise.
If-then plans are the method that worked here, and EV-0048 is the meta-analysis on them. Together those two entries say what a practice in the practice library should look like: not "be more patient this week" but "when X happens, I will do Y."
The limits
Self-reported traits and self-reported daily behavior, so some of the movement may be in how people see themselves. Sixteen weeks, on Big Five traits, mostly with student samples - not leaders at work, and not the twelve character traits. The finding that one intervention failed is a caution as much as the other is an encouragement: wanting to change is necessary and clearly not sufficient, and the method matters more than the motivation. Verified to abstract level.
What we do not say
"You can change your character just by deciding to." One of the two interventions failed. Wanting is the entry condition, not the method.