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Psychological Flexibility: A New Research Agenda

Part II: New research to measure a core element of resilience.

(Start by reading Part I on how our knowledge about psychological flexibility is far less than we think).

A question exists in any attempt to study psychological flexibility: Why are people willing to be flexible? Over the past five years, we created the Personalized Psychological Flexibility Index (PPFI; Kashdan, Disabato, Goodman, Doorley, & McKnight, 2020) to ensure anyone evaluating their PF must provide an explicit answer to this question. The PPFI operationalizes the original definition of PF in the Acceptance and Commitment Therapy literature (Hayes et al., 2004): the ability to respond to distress in ways that facilitate valued goal pursuit.

Rather than measuring distress or vague consequences of negative emotions (e.g., “Emotions cause problems in my life” from the Acceptance and Action Questionnaire-II), the PPFI begins by asking respondents to think about a personally meaningful goal they are currently working towards and answer each item as it relates to this goal. The three dimensions of the PPFI reflect ways of responding to distress during valued goal pursuit ranging from more passive/generally unhealthy (avoidance [reverse scored]; e.g., “When I feel stressed pursuing this goal, I give up”) to increasingly active and healthy (acceptance; e.g., “While pursuing this goal, I try to accept my negative thoughts and feelings rather than resist them”) to less common yet highly adaptive ways of harnessing distress to supercharge goal pursuit (harnessing; e.g., “When faced with obstacles related to this goal, my frustration serves to energize me”). What we uncovered in our factor analyses is a dimension of PF that has only been discussed in the emotion regulation literature: the harnessing of negative emotions for motivation and energy to pursue valued aims. That is, negative emotions or neither good nor bad until you understand how they are used by an individual.

Preliminary evidence shows that the PPFI predicts greater conscientiousness, grit, distress tolerance, subjective happiness, life satisfaction, purpose and meaning in life, psychological needs satisfaction, and less depression, generalized anxiety, and social anxiety (Kashdan et al., in press). Compared to the AAQ-II and Brief Experiential Avoidance Questionnaire (BEAQ), the PPFI is a stronger predictor of outcomes that reflect better living: effective daily goal pursuit (e.g., effort and success, pursuing daily goals closely aligned with one’s purpose in life), the pursuit of broader personal strivings (e.g., feelings of competence, joy, and meaning while pursuing strivings), and the use of adaptive emotion regulation strategies in response to daily stressors (e.g., reappraisal, perspective taking, problem-solving, benefit finding).

Several of our analyses demonstrate that the PPFI is not synonymous with the frequency and intensity that a person endorses negative emotions. First, correlations between the PPFI and psychopathology were moderate. Second, when including both the AAQ-II and PPFI in data analyses, we found that only the AAQ-II predicted unique variance in daily negative emotions. Third, a factor analysis demonstrated that the PPFI subscales load onto their own factor, separate from a second factor that contained negative emotionality (e.g., neuroticism, negative affect, and depression), the AAQ-II, and the BEAQ. If we are to understand people’s responses to distress, we have to tease apart distress itself.

Valued goals are integral to the definition of PF, and indeed, to the design of ACT interventions. Therapists aid people to be in the present moment, open and receptive, and willing to pursue what they care most about despite the presence of pain. To evaluate the effectiveness of these interventions, the measures must match what is supposedly being offered to clients to help them become more resilient. We believe our new measure, the Personalized Psychological Flexibility Index, offers an opportunity to better test the effectiveness of ACT and related acceptance and mindfulness interventions. With improved measurement, scientists can determine whether in fact these interventions are effective, whether any effectiveness is the result of improving people’s PF, and whether modern psychotherapies (e.g., cognitive-behavioral therapy, behavioral activation, interpersonal therapy) differ in their process and mechanisms of action. Existing critiques of measurement approaches used in prior program evaluation efforts suggest that we think we know more than we do about the effectiveness and mechanisms of ACT.

At the core of psychological research and the evaluation of psychological interventions is measurement. To capture the origins, phenomenology, and benefits and costs of PF, it is essential to use measures that capture the construct as theorized. Measurement creation and validation is an iterative process, and any existing and future renderings of PF are born from the creative efforts of researchers entering into uncharted territory. We offer a starting point to improve existing measurements to help understand and enhance PF. With an idiographic approach, where people begin by answering open-ended questions of what personally meaningful goals they are pursuing, and only then answer nomothetic questions of how they handle distress that arises in the pursuit of these goals, we can improve the study of people in the contexts of greatest importance to them. To study PF in a particular domain (e.g., romantic relationships, parenting, work), researchers and clinicians simply have to provide instructions for respondents to focus on their most personally meaningful goal in a particular domain. You can ask people to choose their goals and then answer the nomothetic questions. You can ask athletes to focus on sports-related goals. You can ask people to detail their goals when engaging in political activism. You can ask teams to detail their goals before the start of a new endeavor and follow-up longitudinally.

If we want to understand how people respond to the difficult emotions and thoughts that arise from confronting challenging situations, we need research methods that can capture life as it’s lived with precision. If we want to understand interventions designed to target PF, we require measures that adequately measure the proposed mechanisms and outcomes. We look forward to seeing what researchers uncover and how they continue to build on the shoulders of the revolutionary researchers and interventionists that came before us.


Read about our new research on the Personalized Psychological Flexibility Index here:

Kashdan, T.B., Disabato, D.J., Goodman, F.R., Doorley, J.D., & McKnight, P.E. (2020). Understanding psychological flexibility: A multimethod exploration of pursuing valued goals despite the presence of distress. Psychological Assessment, 32, 829-850.

NOTE: If you want to take or use the measure, download a copy in MSWord with this link. Keep us posted on what you are studying and discovering. We are curious as to how the results of clinical trials of mindfulness and acceptance based interventions such as Acceptance and Commitment Therapy change with this and other modernized assessment devices.

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