Validity And Reliability of The Thai Version of The Family Dermatology Life Quality Index

Objective: This study aimed to investigate the validity and reliability of the Thai version of FDLQI. Materials and Methods: Patients and their accompanying family members attending the Dermatology Outpatient Clinic at Siriraj Hospital were asked to complete the Dermatology Life Quality Index (DLQI), FDLQI, and the global question of their QoL (GQoL). The severity of the disease was assessed by physicians, the patients and the family members of the patients. Results: One hundred family members accompanying 92 patients with dermatological diseases (63% with inflammatory skin diseases and 37% with non-inflammatory skin diseases) were included. The mean age of the family members was 43.5±12.1 years and 70% were women. They had been mostly employed (74%) and graduated from universities (65%). Validity was demonstrated by a positive correlation between FDLQI and GQoL scores (rs=0.695, P<0.001), and between FDLQI and severity of the patient's disease (rs=0.578, P<0.001) as evaluated by family members. The FDLQI showed high internal consistency (Cronbach’s alpha=0.84) and test-retest reliability (ICC= 0.85). Conclusion: The construct validity, internal consistency, and test-retest reliability of the Thai FDLQI demonstrated acceptable validity and reliability. The Thai version of FDLQI can be used to assess the QoL of family members of patients with any dermatological diseases.