Assessing normative cut points through differential item functioning analysis: An example from the adaptation of the Middlesex Elderly Assessment of Mental State (MEAMS) for use as a cognitive screening test in Turkey

BACKGROUND: The Middlesex Elderly Assessment of Mental State (MEAMS) was developed as a screening test to detect cognitive impairment in the elderly. It includes 12 subtests, each having a 'pass score'. A series of tasks were undertaken to adapt the measure for use in the adult population in Turkey and to determine the validity of existing cut points for passing subtests, given the wide range of educational level in the Turkish population. This study focuses on identifying and validating the scoring system of the MEAMS for Turkish adult population. METHODS: After the translation procedure, 350 normal subjects and 158 acquired brain injury patients were assessed by the Turkish version of MEAMS. Initially, appropriate pass scores for the normal population were determined through ANOVA post-hoc tests according to age, gender and education. Rasch analysis was then used to test the internal construct validity of the scale and the validity of the cut points for pass scores on the pooled data by using Differential Item Functioning (DIF) analysis within the framework of the Rasch model. RESULTS: Data with the initially modified pass scores were analyzed. DIF was found for certain subtests by age and education, but not for gender. Following this, pass scores were further adjusted and data re-fitted to the model. All subtests were found to fit the Rasch model (mean item fit 0.184, SD 0.319; person fit -0.224, SD 0.557) and DIF was then found to be absent. Thus the final pass scores for all subtests were determined. CONCLUSION: The MEAMS offers a valid assessment of cognitive state for the adult Turkish population, and the revised cut points accommodate for age and education. Further studies are required to ascertain the validity in different diagnostic groups

Assessment of nocturnal polyuria in patients with spinal cord injury at three different mobilization phases: A multicenter cross-sectional study

Objective To determine the prevalence of nocturnal polyuria (NP) in patients with spinal cord injury (SCI) during three different particular phases, and investigate the impact of injury level and injury type on the prevalence of NP. Design A cross-sectional study. Setting Neurogenic Bladder Study Group from six different rehabilitation centers across the country. Participants 40 patients with SCI. Outcome measures Patients were divided into three groups according to mobilization phase; 1st group included patients confined to bed (n = 14), 2nd group included patients sitting on a wheelchair (n = 19) and 3rd group included patients standing with an assistive ambulation device (n = 7). NP was assessed by nocturnal polyuria index (NPi) and nocturnal urine production (NUP) indexes. Results No significant difference was found between the groups (P = 0.312 for NPi and P = 0.763 for NUP) in terms of the presence of NP according to their mobilization phase. The night and 24-hour urine volumes showed no significant difference between the groups (P = 0.907 and P = 0.395 respectively). The NPi and NUP values did not show a significant difference between male and female patients (P = 0.826, P = 0.364 respectively), patients with the injury level of >= T6 and <T6 (P = 0.236, P = 1.00) and patients with a complete and incomplete injury (P = 0.826, P = 0.283). Conclusion In this study, NP was found to be a common problem in patients with SCI regardless of their mobilization phase, injury level and injury type. It was revealed that both NPi and NUP parameters could be used to determine the prevalence of NP in this patient group