G.H.M.B. van Rens

Rationale, methods and baseline demographics of the Bhaktapur Glaucoma Study

Background:  To describe the methodology and baseline data of a population‐based study designed to determine the prevalence of glaucoma and to study the risk factors for glaucoma development in a Nepali population.

Low vision rehabilitation plans comparing two intake methods.

Purpose. This qualitative study investigates possible differences in identified rehabilitation needs indicated by the usual intake procedures at a Multidisciplinary Rehabilitation Center (MRC) for visually impaired persons compared with those indicated by the use of a structured Dutch version [based on the International Classification of the Disability, Functioning and Health (ICF)] of the Activity Inventory (D-AI). Methods. Twenty patients who enrolled at the MRC received a D-AI assessment by telephone, in addition to the usual intake. All patients received usual care, based on rehabilitation needs identified by the usual intake procedure at the MRC. Rehabilitation needs identified at the MRC were obtained from patient files retrospectively and were compared with rehabilitation needs identified by the D-AI. Results. The mean number of rehabilitation needs reported in the patient files was 6.9 (±5.1) vs. 24.0 (±11.2) using the D-AI. Only 22.6% (±14.3) of the rehabilitation needs identified by the D-AI were present in the patient files; 79.3% (±28.2) of the rehabilitation needs reported in the patient files were identified by the D-AI. Overall agreement corrected for chance between both intake methods revealed a fair Cohen kappa of 0.27. Conclusions. At the MRC, more needs were revealed using the D-AI compared with the usual intake procedure. The systematic character of the D-AI prevents important topics being overlooked. In the usual intake, it was not clear whether needs were investigated from the patients perspective. This may hamper (medical) communication and shared decision making about the rehabilitation program that needs to be followed. Moreover, using the unstructured information from the patient files makes it difficult to evaluate rehabilitation outcomes. With the D-AI, although an extensive overview of rehabilitation needs is produced, it remains difficult to focus on the most relevant needs. However, after assessment with the D-AI, all aspects of the ICF, Disability, and Health scheme can be discussed in a process of shared decision making, which leads to the final determination of rehabilitation goals.

Psychometric analyses to improve the Dutch ICF Activity Inventory.

Purpose In the past, rehabilitation centers for the visually impaired used unstructured or semistructured methods to assess rehabilitation needs of their patients. Recently, an extensive instrument, the Dutch ICF Activity Inventory (D-AI), was developed to systematically investigate rehabilitation needs of visually impaired adults and to evaluate rehabilitation outcomes. The purpose of this study was to investigate the underlying factor structure and other psychometric properties to shorten and improve the D-AI. Methods The D-AI was administered to 241 visually impaired persons who recently enrolled in a multidisciplinary rehabilitation center. The D-AI uses graded scores to assess the importance and difficulty of 65 rehabilitation goals. For high-priority goals (e.g., daily meal preparation), the difficulty of underlying tasks (e.g., read recipes, cut vegetables) was assessed. To reduce underlying task items (>950), descriptive statistics were investigated and factor analyses were performed for several goals. The internal consistency reliability and test-retest reliability of the D-AI were investigated by calculating Cronbach &agr; and Cohen (weighted) &kgr;. Finally, consensus-based discussions were used to shorten and improve the D-AI. Results Except for one goal, factor analysis model parameters were at least reasonable. Internal consistency reliability was satisfactory (range, 0.74 to 0.93). In total, 60% of the 65 goal importance items and 84.4% of the goal difficulty items showed moderate to almost perfect &kgr; values (≥0.40). After consensus-based discussions, a new D-AI was produced, containing 48 goals and less than 500 tasks. Conclusions The analyses were an important step in the validation process of the D-AI and to develop a more feasible assessment tool to investigate rehabilitation needs of visually impaired persons in a systematic way. The D-AI is currently implemented in all Dutch rehabilitation centers serving all visually impaired adults with various rehabilitation needs.

Infantile nystagmus syndrome is associated with inefficiency of goal-directed hand movements

PURPOSE The effect of infantile nystagmus syndrome (INS) on the efficiency of goal-directed hand movements was examined. METHODS We recruited 37 children with INS and 65 control subjects with normal vision, aged 4 to 8 years. Participants performed horizontally-oriented, goal-directed cylinder displacements as if they displaced a low-vision aid. The first 10 movements of 20 back-and-forth displacements in a trial were performed between two visually presented target areas, and the second 10 between remembered target locations (not visible). Motor performance was examined in terms of movement time, endpoint accuracy, and a harmonicity index reflecting energetic efficiency. RESULTS Compared to the control group, the children with INS performed the cylinder displacements more slowly (using more time), less accurately (specifically in small-amplitude movements), and with less harmonic acceleration profiles. Their poor visual acuity proved to correlate with slower and less accurate movements, but did not correlate with harmonicity. When moving between remembered target locations, the performance of children with INS was less accurate than that of the children with normal vision. In both groups, movement speed and harmonicity increased with age to a similar extent. CONCLUSIONS Collectively, the findings suggest that, in addition to the visuospatial homing-in problems associated with the syndrome, INS is associated with inefficiency of goal-directed hand movements. ( http://www.trialregister.nl number, NTR2380.).

Development of a Standardized Protocol for Orientation and Mobility Training in Visually Impaired Older People

This meeting discusses New approaches to engaging older adults in lifelong learning. It was presented at the Gerontological Society of America 61st Annual Scientific Meeting in 2008.

Diabetes mellitus: A risk factor affecting visual outcome in branch retinal vein occlusion

Purpose The prognosis of visual acuity (VA) after branch retinal vein occlusion (BRVO) in patients with diabetes mellitus is unknown compared to the VA in non-diabetic patients with BRVO. The aim of this study was to evaluate the visual outcome of BRVO in diabetic and non-diabetic patients. Methods A retrospective case-control study of diabetic and non-diabetic patients with BRVO was performed. VA and commonly known risk factors and complications of BRVO were compared in a follow-up period of at least 1 year. Results A total of 28 eyes of patients with diabetes and 49 eyes of non-diabetic patients with BRVO were included. One year after BRVO, the VA in the patients with diabetes decreased significantly more than that of the non-diabetic patients. During the second year after BRVO, the VA did not change significantly in either group. BRVO in patients with diabetes occurs at an earlier age. Diabetic patients needed more outpatient visits. Conclusions The VA 1 year after BRVO in patients with diabetes is worse compared to the VA in patients without diabetes. The VA stabilizes 1 year after onset in both groups. Diabetic patients tend to need more frequent follow-up in order to treat the sequelae of BRVO.

Science Leaks: A Signal to Improve Data Protection in Scientific Research

Hello sir, I’m calling regarding a recent scientific study in which you are participating. I want to thank you for taking part in this study by offering you a present. Only a small amount of postage costs need to be paid to receive this present, for which I will need your bank account number.” Recently, an older visually impaired participant of a clinical trial conducted by the VU University Medical Centre in Amsterdam (which will be referred to as the university hospital in this article) received this harassing telephone message from someone unknown to the research team. Fortunately, the participant did not respond to