[Speech therapy assessment: field study on psychometric properties, practicability, acceptance and process quality].

OBJECTIVE

to investigate the internal consistency, responsiveness, discriminative validity, practicability, acceptance and process quality of a recently developed Speech Therapy Assessment (STA) under routine work conditions of speech and language therapists in German speaking countries. Since standardised, generic and ICF-oriented assessment tools for documentation and evaluation of speech therapy interventions for adult clients are missing in German speaking countries and existing tests cover only sub-areas, the STA has been developed in the years 1995 to 2002. By means of different domains, speech and language therapists assess client (1) communication, (2) aphasia, (3) speech apraxia, (4) dysarthria and (5) dysphagia as well as (6) her or his dealing with corresponding disabilities.

METHODS

17 therapists from 14 institutions applied the STA to 260 adult clients with language, speaking or swallowing disorders. The clients were included in the study consecutively over a period of 7 month. After this period, the therapists completed a questionnaire regarding the benefit and practicability of the STA. Cronbach alpha was calculated as indicator for internal consistency, effect sizes (standardised response means) for responsiveness and ROC values for discriminative validity. The answers of the questionnaire about the benefit of the STA were evaluated both, quantitatively and qualitatively.

RESULTS

The internal consistency and discriminative validity were high (Cronbach alpha: 0.79 to 0.95; ROC-values: 0.84 to 0.98). Effect sizes regarding responsiveness were moderate (standardised response means: 0.46 to 0.78). On a 5-step Likert scale (1 = very good, 5 = inadequate), the therapists rated the average (standard deviation) benefit of the STA with: practicability 2.6 (1.2), acceptance 2.8 (1.3), impact on diagnostics 2.8 (1.3), impact on finding therapeutic goals 3.5 (1.2), impact on communication with other rehabilitation partners 2.7 (1.5) and overall judgement 2.6 (0.9).

CONCLUSION

The STA fulfils essential quality criteria of the classical test theory. The involved therapists assessed the benefit of the STA as satisfactory. In addition, they pointed out concrete improvement potential for the implementation in practice. It is planed to investigate a refined version of the STA in a multi centre validation study.