Background: Previous studies found that 40-60% of the sarcoidosis patients suffer from small fiber neuropathy (SFN), substantially affecting quality of life. SFN is difficult to diagnose, as a gold standard is still lacking. The need for an easily administered screening instrument to identify sarcoidosis-associated SFN symptoms led to the development of the SFN Screening List (SFNSL). The usefulness of any questionnaire in clinical management and research trials depends on its interpretability. Obtaining a clinically relevant change score on a questionnaire requires that the smallest detectable change (SDC) and minimal important difference (MID) are known. Objectives: The aim of this study was to determine the SDC and MID for the SFNSL in patients with sarcoidosis. Methods: Patients with neurosarcoidosis and/or sarcoidosis-associated SFN symptoms (N=138) included in the online Dutch Neurosarcoidosis Registry participated in a prospective, longitudinal study. Anchor-based and distribution-based methods were used to estimate the MID and SDC, respectively. Results: The SFNSL was completed both at baseline and at 6-months’ follow-up by 89/138 patients. A marginal ROC curve (0.6) indicated cut-off values of 3.5 points, with 73% sensitivity and 49% specificity for change. The SDC was 11.8 points. Conclusions: The MID on the SFNSL is 3.5 points for a clinically relevant change over a 6-month period. The MID can be used in the follow-up and management of SFN-associated symptoms in patients with sarcoidosis, though with some caution as the SDC was found to be higher.
The wheelchair ergometer (Lode Esseda) can be used to monitor propulsion variables of wheelchair users, for example to evaluate wheelchair adaptations. In order to interpret the outcomes of the measurements and to support clinical decision making, it is important to distinguish real changes in propulsion technique and physiological outcomes from measurement errors.
OBJECTIVE: Ever since Engel's Biopsychosocial Model (1977) emotions, thoughts, beliefs and behaviors are accepted as important factors of health. The Brief Illness Perception Questionnaire (Brief IPQ) assesses these beliefs. Aim of this study was to cross-culturally adapt the Brief IPQ into the Brief IPQ Dutch Language Version (Brief IPQ-DLV), and to assess its face validity, content validity, reproducibility, and concurrent validity. METHODS: Beaton's guideline was used for cross-culturally adaptation. Face and content validity were assessed in 25 patients, 15 physiotherapists and 24 first-grade students. Reproducibility was established in 27 individuals with chronic obstructive pulmonary disease using Cohen's kappa coefficient (K(w)) and the Smallest Detectable Change (SDC). Concurrent validity was assessed in 163 patients visiting 11 different physical therapists. RESULTS: The Brief IPQ-DLV is well understood by patients, health care professionals and first-grade students. Reliability at 1 week for the dimensions Consequences, Concern and Emotional response K(w)>0.70, for the dimensions Personal control, Treatment control, Identity, K(w)<0.70. A time interval of 3 weeks, reliability coefficients were lower for almost all dimensions. SDC was between 2.45 and 3.37 points for individual measurement purposes and between 0.47 and 0.57 points for group evaluative measurement purposes. Concurrent validity showed significant correlations (P<.05) for four out of eight illness perceptions (IPs) dimensions. CONCLUSION: The face and content properties were found to be acceptable. The reproducibility and concurrent validity needs further investigated
