The Forgotten Joint Score (FJS) is a 12-item patient reported outcome measurement instrument. It was developed with classical test theory, without testing assumptions such as unidimensionality (all items reflect one underlying factor), appropriate weighting of each item, no differential item function (DIF, different groups answer the same way), and monotonicity (people with higher function have higher score). We applied item response theory (IRT) to improve the validity of FJS to contemporary standards to optimise it for ongoing use. Does the FJS reflect one latent trait? Can an IRT model be fitted to the FJS to provide interval-scaled measurement?Abstract
Background
Research Questions
This study investigates whether primary knee arthroplasty (KA) restores health-related quality of life (HRQoL) to levels expected in the general population. This retrospective case-control study utilises two sources: patients undergoing primary KA from a University Teaching hospital; and individual-level data from the Health Survey for England which was used to represent the General Population. Propensity score matching was used to balance covariates (sex, age and body mass index (BMI)) and facilitate group comparisons. Two matched cohorts with 3029 patients each were obtained for the adjusted analyses (median age 70.3 interquartile range (IQR) 64–77; Female sex 3233 (53.4%); median BMI 29.7 IQR 26.5-33.7). HRQoL was measured using the three-level version of the EuroQol 5-Dimensions’ (EQ-5D-3L) Index and EQ-VAS scores.Abstract
INTRODUCTION
METHODOLOGY
A pragmatic, multicentre, parallel-group, randomised controlled trial to determine whether the intervention is superior to comparator 20 NHS HospitalsAbstract
Design
Setting
The aim of the present study was to look at survivorship and patient satisfaction of a fixed bearing unicompartmental knee arthroplasty with an all-polyethylene tibial component. We report the survivorship of 91 fixed bearing unicompartmental arthroplasties with all-polyethylene tibial components (Preservation DePuy UK), which were used for medial compartment osteoarthritis in 79 patients between 2004 and 2007. The satisfaction level of patients who had not undergone revision of the implant was also recorded. For comparison, we reviewed 49 mobile bearing unicompartmental arthroplasties (Oxford UKA Biomet UK Ltd), which had been used in 44 patients between 1998 and 2007.Purpose
Materials and Methods