The Structured Interview for Competency and Incompetency Assessment Testing and Ranking Inventory (SICIATRI) was studied as a guide to assess the competency for giving informed consent to treatment. The validity and reliability of this instrument was examined among 48 psychiatric and medical inpatients (J. Clinical Psychology, Vol. 53(5), 443-450 (1997)). Results showed a relatively high reliability and concurrent validity which suggest SICIATRI's utility in a variety of clinical decision-making settings.
SICIATRI consists of 12 items measuring the patient's capacity to give informed consent to a variety of clinical procedures. These items measure different aspects of competency and are ordered in such a way that "both the interviewer and the patients can feel it to be as natural as possible." Among the 12 items are "Is aware that he/she was informed," "Does not waive the right to decide," "Understands the alternative treatments," and "Wants to get better." It took 20 minutes to conduct an interview.
After completing the interview, the rater classified the patient's competency into five categories according to Ranking Inventory for Competency: level 0, completely incompetent, to level 4, completely competent. This algorithm was based on the assumption that the competency level could be plotted on a continuum of the patient's cognitive capacity.
As the external criterion against which to examine the concurrent validity of the SICIATRI, the Disclosure Consent Check List (DCCL) was completed by the attending physician to describe the nature and amount of knowledge disclosed to or possessed by the patient. The items were almost identical to those in the SICIATRI. In the last section of the DCCL-the Global Assessment of Competency-the attending physician rated the patient with two anchor points: competent or incompetent.
When the kappa coefficients between the two interviewers were calculated for the 12 items of SICIATRI to assess the interrater reliability, most items showed good kappa coefficients. Concurrent validity of SICIATRI was assessed using the Statistical Package for Social Sciences. "Fairly good sensitivity and specificity" were shown between the score of the Ranking Inventory for Competency (interviewer) and that of the Global Assessment of Competency (attending physician).
Nevertheless, case illustrations of inadequate or incorrect assessments of patients' competency by attending physicians led the researchers to conclude that the attendings are prone to giving more emphasis to the general competency than to the patient's capacity specific to the current illness and the proposed treatment. This consideration impacts assessments of other task competencies, such as criminal and testamentary, as well.
Given the frequency of these clinical dilemmas in practice, this study is arguably relevant to every hospitalized and medicated patient. Validating such a standardized scale oriented toward medical decision making would be of great benefit to patient care.
