The unidimensionality of the five Brain Injury Rehabilitation Trust Personality Questionnaires (BIRT-PQs) may be improved: preliminary evidence from classical psychometrics

ABSTRACT

Objective: To assess the internal construct validity (ICV) of the five Brain Injury Rehabilitation Trust Personality Questionnaires (BIRT-PQ) with Classical Test Theory methods.

Methods: Multicenter cross-sectional study involving 11 Italian rehabilitation centers. BIRT-PQs were administered to patients with severe Acquired Brain Injury and their respective caregivers. ICV was assessed by the mean of an internal consistency analysis (ICA) and a Confirmatory Factor Analysis (CFA).

Results: Data from 154 patients and their respective caregivers were pooled, giving a total sample of 308 subjects. Despite good overall values (alphas ranging from 0.811 to 0.937), the ICA revealed that several items within each scale did not contribute as expected to the total score. This result was confirmed by the CFA, which showed the misfit of the data to a unidimensional model (RMSEA ranging from 0.077 to 0.097). However, after accounting for local dependency found within the data, fitness to a unidimensional model improved significantly (RMSEA ranging from 0.050 to 0.062).

Conclusion: Despite some limitations, our analyses demonstrated the lack of ICV for the BIRT-PQ total scores. It is envisaged that a more comprehensive ICV analysis will be performed with Rasch analysis, aiming to improve both the measurement properties and the administrative burden of each BIRT-PQ.

KEYWORDS:

• Brain Injuries
• Behavioral Symptoms
• Personality Assessment
• Outcome Assessment (Health care)
• Psychometrics
• Rehabilitation

Acknowledgments

The authors want to thank Maria Paola Ciurli, Elisa Scarano, Maria Daniela Lo Sapio for their help in collecting the data.

Declaration of interest

The authors report no conflict of interest.

Data availability statement

The data that support the findings of this study are available from the corresponding author [LP], upon reasonable request.

Notes

1. Centro Cardinal Ferrari, Fontanellato, Parma; Clinica di Riabilitazione Toscana Spa, Montevarchi, Arezzo; Istituto Clinico Quarenghi, San Pellegrino Terme, Bergamo; Centro Puzzle, Turin; Istituto Santo Stefano, Porto Potenza Picena, Ancona; IRCCS Salvatore Maugeri, Telese, Benevento; Ospedale Sacro Cuore Don Calabria, Negrar, Verona; Ospedale Papa Giovanni XXIII, Bergamo; Casa di Cura del Policlinico, Milan; Fondazione Santa Lucia, Rome; Viglietta, Cuneo.

Additional information

Funding

LP was (partially) supported by funding of the Italian Ministry of Health (Ricerca Corrente)