Structural validity of the Finnish Manchester-Oxford Foot Questionnaire (MOXFQ) using the Rasch model.

BACKGROUND: The 16-item patient-reported Manchester-Oxford Foot Questionnaire (MOXFQ) with subscales of pain, social interactions, and walking/standing has been claimed for strongest scientific evidence in measuring foot and ankle complaints. This study tests the validity of the Finnish MOXFQ for orthopaedic foot and ankle population using the Rasch analysis. METHODS: We translated the MOXFQ into Finnish and used that translation in our study. MOXFQ scores were obtained from 183 patients. Response category distribution, item fit, coverage, targeting, item dependency, ability to measure latent trait (unidimensionality), internal consistency (Cronbach's alpha), and person separation index (PSI) were analyzed. RESULTS: Fifteen of the items had ordered response categories and/or sufficient fit statistics. The subscales provided coverage and targeting. Some residual correlation was noted. Removing one item in the pain subscale led to a unidimensional structure. Alphas and PSIs ranged between 0.68-0.90 and 0.67-0.92, respectively. CONCLUSIONS: Despite some infractions of the Rasch model, the instrument functioned well. The subscales of the MOXFQ are meaningful for assessing patient-reported complaints and outcomes in orthopaedic foot and ankle population.

Amyloid and tau proteins in cortical brain biopsy and Alzheimer's disease.

OBJECTIVE: Amyloid-ß(Aß) aggregates are presumed to be found in the brain at an early stage of Alzheimer's disease (AD) but have seldom been assessed by brain biopsy during life in often elderly patients. METHODS: Between 1991 and 2006 we evaluated 468 patients with suspected normal pressure hydrocephalus with intraventricular pressure monitoring and a right frontal cortical biopsy sample immunostained for Aß and hyperphosphorylated tau (HPτ). Adequate samples and the clinical follow-up data until death or the end of 2008, available in 433 cases, were reviewed for the clinical signs of dementia, including AD. Logistic regression analysis was used to analyze whether Aß and/or HPτ in the biopsy samples obtained during life predicted development of cognitive impairment, in particular, AD. RESULTS: Of the 433 frontal cortical samples, 42 (10%) displayed both Aß and HPτ, 144 (33%) Aß only, and 247 (57%) neither Aß nor HPτ. In a median follow-up time of 4.4 years, 94 patients (22%) developed clinical AD. The presence of both Aß and HPτ was strongly associated (odds ratio [OR], 68.2; 95% confidence interval [CI], 22.1-210) and Aß alone significantly associated (OR, 10.8; 95% CI, 4.9-23.8) with the clinical diagnosis of AD. INTERPRETATION: This is the largest follow-up study of patients assessed for the presence of Aß and HPτ in frontal cortical brain biopsy samples. 1) The presence of Aß and HPτ spoke strongly for the presence or later development of clinical AD; 2) Aß alone was suggestive of AD; and 3) the absence of Aß and HPτ spoke against a later clinical diagnosis of AD.