Validity and Reliability of the Pictures of Facial Affect (POFA) in Healthy People and Patients with Essential Tremor in the Turkish Population.

Introduction: This study aimed to conduct the validity and reliability of the (Pictures of Facial Affect) POFA test for the Turkish population and contribute to increasing the number of tests that are still insufficient in our country. Methods: This descriptive, randomized controlled study was conducted in two steps, namely Step 1 (Pilot Study and Validity Studies) and Step 2 (Reliability Study Step). The number of participants was planned regarding the original study by which the POFA test was developed. The EYES test was also used for comparison. In the pilot study, the most widely identified emotions from 47 of 110 photos in the POFA test were chosen as the new POFA picture set to be used in the reliability and validity study under the name "POFA Test Short Form". A total of 100 participants, including 82 healthy volunteers and 18 essential tremor (ET) patients, were enrolled in the first step of the study. Another cohort of 22 healthy volunteers was enrolled in the second step of the study for test-retest reliability analysis. Results: A significant positive correlation was found between the total POFA Test Short Form and EYES Test scores in the healthy volunteer group in terms of criterion-related validity (r=0.44, p<0.01). There were statistically significant differences between healthy volunteers and ET groups regarding EYES Total, POFA Total, POFA Sadness, POFA Anger, and POFA Neutral scores. It was observed that the 47-item POFA Test Short Form total score showed skewness and kurtosis, which demonstrated suitability for clinical use. Conclusion: The POFA Test Short Form was found to be a valid and reliable assessment tool in the Turkish population to be used in studies on emotion recognition and was shown to be beneficial for the discrimination of healthy individuals and ET patients.