Initial Psychometric Assessment of a Functional Oral Intake Scale for Dysphagia in Stroke Patients

Crary MA, Carnaby Mann GD, Groher ME. Initial psychometric assessment of a functional oral intake scale for dysphagia in stroke patients. Objective To report on the development and psychometric evaluation of a clinical scale to document change in functional oral intake of food and liquid in stroke patients. Design Validity and reliability study. Setting Tertiary care, academic medical center, metropolitan stroke unit. Participants Acute stroke patients (N=302). Interventions Not applicable. Main Outcome Measures Interrater reliability, validity, and sensitivity to change assessments were completed on a 7-point ordinal scale—the Functional Oral Intake Scale (FOIS)—developed to document the functional level of oral intake of food and liquid in stroke patients. Interrater reliability was drawn from FOIS ratings applied to dietary information from patient medical charts. Consensual validity was estimated by rankings from judges against predefined scale scores. Criterion validity was evaluated by comparison to the Modified Rankin Scale, the Modified Barthel Index, and Mann Assessment of Swallowing Ability. Cross-validation was assessed via comparison to 2 physiologic measures of swallowing function. Change in functional oral intake over time was assessed descriptively by applying the scale to dietary information from a cohort of 302 acute stroke patients followed up for 6 months. Results Interrater reliability was high, with perfect agreement on 85% of ratings. Kappa statistics ranged from .86 to .91. Consensual validity was high (.90). Criterion validity was high at onset and 1 month poststroke. Significant associations were identified between the FOIS and stroke handicap scales. The FOIS was significantly associated with 2 physiologic measures of swallowing. Scores on the FOIS from the cohort of stroke patients showed a shift toward increased oral intake over a 6-month period. Conclusions The FOIS had adequate reliability, validity, and sensitivity to change in functional oral intake. These findings suggest that the FOIS may be appropriate for estimating and documenting change in the functional eating abilities of stroke patients over time.