Validation of the Amharic Version of the Full and Short Form of the Trust in Oncologist Scale Among Cervical Cancer Patient.

Abstract

Background: The Trust in Oncologist Scale (TiOS) is a tool used to measure cancer patients' self-reported trust in their oncologists. It has been validated in Dutch, English, Japanese, and Italian.

Aims: This study aims to validate the Amharic version of the tool and develop its short form.

Methods and results: A cross-sectional study design was employed among 197 cervical cancer patients at a tertiary teaching hospital in Ethiopia (February to April 2025). Internal consistency, convergent validity, and the structural validity of both the full scale and short form of the Amharic TiOS were tested. The Amharic TiOS mean score was 69.95 (±9.41, range 34-90), with a mean score of 3.89 (±0.52). Neither the four-factor nor the one-factor models fit the full scale. A unidimensional five-item solution emerged with two possible item sets: (1, 6, 15, 14, and 18) and (1, 3, 15, 14, and 18). To preserve content validity, the second set was selected. This five-item scale yielded a mean score of 4.01 (±0.57), strong internal consistency (α = 0.88), and significant correlations with time since diagnosis (r = 0.20, p < 0.05), perceived levels of shared decision-making (r = 0.38, p < 0.001), and health literacy (r = -0.32, p < 0.01).

Conclusion: Unlike the full Amharic scale, the short form demonstrated acceptable psychometric properties and can be used to assess trust in both clinical practice and research settings among cervical cancer patients in Ethiopia.