Catharina Gerarda Maria Groothuis-Oudshoorn

Systematic review of the effect of robot-aided therapy on recovery of the hemiparetic arm after stroke

A limited number of clinical studies have examined the effect of poststroke rehabilitation with robotic devices on hemiparetic arm function. We systematically reviewed the literature to assess the effect of robot-aided therapy on stroke patients upper-limb motor control and functional abilities. Eight clinical trials were identified and reviewed. For four of these studies, we also pooled short-term mean changes in Fugl-Meyer scores before and after robot-aided therapy. We found that robot-aided therapy of the proximal upper limb improves short- and long-term motor control of the paretic shoulder and elbow in subacute and chronic patients; however, we found no consistent influence on functional abilities. In addition, robot-aided therapy appears to improve motor control more than conventional therapy.

Statistical Methods for the Analysis of Discrete Choice Experiments: A Report of the ISPOR Conjoint Analysis Good Research Practices Task Force

Conjoint analysis is a stated-preference survey method that can be used to elicit responses that reveal preferences, priorities, and the relative importance of individual features associated with health care interventions or services. Conjoint analysis methods, particularly discrete choice experiments (DCEs), have been increasingly used to quantify preferences of patients, caregivers, physicians, and other stakeholders. Recent consensus-based guidance on good research practices, including two recent task force reports from the International Society for Pharmacoeconomics and Outcomes Research, has aided in improving the quality of conjoint analyses and DCEs in outcomes research. Nevertheless, uncertainty regarding good research practices for the statistical analysis of data from DCEs persists. There are multiple methods for analyzing DCE data. Understanding the characteristics and appropriate use of different analysis methods is critical to conducting a well-designed DCE study. This report will assist researchers in evaluating and selecting among alternative approaches to conducting statistical analysis of DCE data. We first present a simplistic DCE example and a simple method for using the resulting data. We then present a pedagogical example of a DCE and one of the most common approaches to analyzing data from such a question format-conditional logit. We then describe some common alternative methods for analyzing these data and the strengths and weaknesses of each alternative. We present the ESTIMATE checklist, which includes a list of questions to consider when justifying the choice of analysis method, describing the analysis, and interpreting the results.

Therapeutic Effect of an Implantable Peroneal Nerve Stimulator in Subjects With Chronic Stroke and Footdrop: A Randomized Controlled Trial

Background and Purpose:Footdrop, characterized by a persons inability to raise the foot at the ankle, is a common problem in patients with stroke. A randomized controlled trial was performed to determine the therapeutic effect of using a new implantable, 2-channel peroneal nerve stimulator for 6 months versus an ankle-foot orthosis (AFO). Subjects: Twenty-nine patients with chronic stroke and footdrop participated in the study. The mean time from stroke was 7.3 years (SD=7.3), and all subjects were community ambulators. Methods: The study used a randomized controlled trial design. The functional electrical stimulation (FES) group received the implantable stimulation system for correction of their footdrop. The control group continued using their conventional walking device (ie, AFO, orthopedic shoes, or no walking device). All subjects were measured at baseline and at weeks 4, 8, 12, and 26 in the gait laboratory. The therapeutic effect of FES on the maximum value of the root mean square (RMSmax) of the tibialis anterior (TA) muscle with both flexed and extended knees and walking speed were selected as the primary outcome measures. The RMSmax of the peroneus longus (PL), gastrocnemius (GS), and soleus (SL) muscles with both flexed and extended knees and muscle activity of the TA muscle of the affected leg during the swing phase of gait were selected as secondary outcome measures. Results: A significantly higher RMSmax of the TA muscle with extended knee was found after using FES. No change in walking speed was found when the stimulator was not switched on. A significantly increased RMSmax of the GS muscle with both flexed and extended knees was found after using FES. Discussion and Conclusion: Functionally, no therapeutic effect of implantable peroneal nerve stimulation was found. However, the significantly increased voluntary muscle output of the TA and GS muscles after the use of FES suggests that there was a certain extent of plasticity in the subjects in this study.

Helmet therapy in infants with positional skull deformation: randomised controlled trial

Objective To determine the effectiveness of helmet therapy for positional skull deformation compared with the natural course of the condition in infants aged 5-6 months. Design Pragmatic, single blinded, randomised controlled trial (HEADS, HElmet therapy Assessment in Deformed Skulls) nested in a prospective cohort study. Setting 29 paediatric physiotherapy practices; helmet therapy was administered at four specialised centres. Participants 84 infants aged 5 to 6 months with moderate to severe skull deformation, who were born after 36 weeks of gestation and had no muscular torticollis, craniosynostosis, or dysmorphic features. Participants were randomly assigned to helmet therapy (n=42) or to natural course of the condition (n=42) according to a randomisation plan with blocks of eight. Interventions Six months of helmet therapy compared with the natural course of skull deformation. In both trial arms parents were asked to avoid any (additional) treatment for the skull deformation. Main outcome measures The primary outcome was change in skull shape from baseline to 24 months of age assessed using plagiocephalometry (anthropometric measurement instrument). Change scores for plagiocephaly (oblique diameter difference index) and brachycephaly (cranioproportional index) were each included in an analysis of covariance, using baseline values as the covariate. Secondary outcomes were ear deviation, facial asymmetry, occipital lift, and motor development in the infant, quality of life (infant and parent measures), and parental satisfaction and anxiety. Baseline measurements were performed in infants aged between 5 and 6 months, with follow-up measurements at 8, 12, and 24 months. Primary outcome assessment at 24 months was blinded. Results The change score for both plagiocephaly and brachycephaly was equal between the helmet therapy and natural course groups, with a mean difference of −0.2 (95% confidence interval −1.6 to 1.2, P=0.80) and 0.2 (−1.7 to 2.2, P=0.81), respectively. Full recovery was achieved in 10 of 39 (26%) participants in the helmet therapy group and 9 of 40 (23%) participants in the natural course group (odds ratio 1.2, 95% confidence interval 0.4 to 3.3, P=0.74). All parents reported one or more side effects. Conclusions Based on the equal effectiveness of helmet therapy and skull deformation following its natural course, high prevalence of side effects, and high costs associated with helmet therapy, we discourage the use of a helmet as a standard treatment for healthy infants with moderate to severe skull deformation. Trial registration Current Controlled Trials ISRCTN18473161.

A Review and Classification of Approaches for Dealing with Uncertainty in Multi-Criteria Decision Analysis for Healthcare Decisions

Multi-criteria decision analysis (MCDA) is increasingly used to support decisions in healthcare involving multiple and conflicting criteria. Although uncertainty is usually carefully addressed in health economic evaluations, whether and how the different sources of uncertainty are dealt with and with what methods in MCDA is less known. The objective of this study is to review how uncertainty can be explicitly taken into account in MCDA and to discuss which approach may be appropriate for healthcare decision makers. A literature review was conducted in the Scopus and PubMed databases. Two reviewers independently categorized studies according to research areas, the type of MCDA used, and the approach used to quantify uncertainty. Selected full text articles were read for methodological details. The search strategy identified 569 studies. The five approaches most identified were fuzzy set theory (45xa0% of studies), probabilistic sensitivity analysis (15xa0%), deterministic sensitivity analysis (31xa0%), Bayesian framework (6xa0%), and grey theory (3xa0%). A large number of papers considered the analytic hierarchy process in combination with fuzzy set theory (31xa0%). Only 3xa0% of studies were published in healthcare-related journals. In conclusion, our review identified five different approaches to take uncertainty into account in MCDA. The deterministic approach is most likely sufficient for most healthcare policy decisions because of its low complexity and straightforward implementation. However, more complex approaches may be needed when multiple sources of uncertainty must be considered simultaneously.

Does technique matter; a pilot study exploring weighting techniques for a multi-criteria decision support framework

BackgroundThere is an increased interest in the use of multi-criteria decision analysis (MCDA) to support regulatory and reimbursement decision making. The EVIDEM framework was developed to provide pragmatic multi-criteria decision support in health care, to estimate the value of healthcare interventions, and to aid in priority-setting. The objectives of this study were to test 1) the influence of different weighting techniques on the overall outcome of an MCDA exercise, 2) the discriminative power in weighting different criteria of such techniques, and 3) whether different techniques result in similar weights in weighting the criteria set proposed by the EVIDEM framework.MethodsA sample of 60 Dutch and Canadian students participated in the study. Each student used an online survey to provide weights for 14 criteria with two different techniques: a five-point rating scale and one of the following techniques selected randomly: ranking, point allocation, pairwise comparison and best worst scaling.ResultsThe results of this study indicate that there is no effect of differences in weights on value estimates at the group level. On an individual level, considerable differences in criteria weights and rank order occur as a result of the weight elicitation method used, and the ability of different techniques to discriminate in criteria importance. Of the five techniques tested, the pair-wise comparison of criteria has the highest ability to discriminate in weights when fourteen criteria are compared.ConclusionsWhen weights are intended to support group decisions, the choice of elicitation technique has negligible impact on criteria weights and the overall value of an innovation. However, when weights are used to support individual decisions, the choice of elicitation technique influences outcome and studies that use dissimilar techniques cannot be easily compared. Weight elicitation through pairwise comparison of criteria is preferred when taking into account its superior ability to discriminate between criteria and respondents’ preferences.

Preferences for Colorectal Cancer Screening Techniques and Intention to Attend: a Multi-Criteria Decision Analysis

BackgroundDespite the expected health benefits of colorectal cancer screening programs, participation rates remain low in countries that have implemented such a screening program. The perceived benefits and risks of the colorectal cancer screening technique are likely to influence the decision to attend the screening program. Besides the diagnostic accuracy and the risks of the screening technique, which can affect the health of the participants, additional factors, such as the burden of the test, may impact the individuals’ decisions to participate. To maximise the participation rate of a screening program for a new colorectal cancer program in the Netherlands, it is important to know the preferences of the screening population for alternative screening techniques.ObjectiveThe aim of this study was to explore the impact of preferences for particular attributes of the screening tests on the intention to attend a colorectal cancer screening program.MethodsWe used a web-based questionnaire to elicit the preferences of the target population for a selection of colon-screening techniques. The target population consisted of Dutch men and women aged 55–75xa0years. The analytic hierarchy process (AHP), a technique for multi-criteria analysis, was used to estimate the colorectal cancer screening preferences. Respondents weighted the relevance of five criteria, i.e. the attributes of the screening techniques: sensitivity, specificity, safety, inconvenience, and frequency of the test. With regard to these criteria, preferences were estimated between four alternative screening techniques, namely, immunochemical fecal occult blood test (iFOBT), colonoscopy, sigmoidoscopy, and computerized tomographic (CT) colonography. A five-point ordinal scale was used to estimate the respondents’ intention to attend the screening. We conducted a correlation analysis on the preferences for the screening techniques and the intention to attend.ResultsWe included 167 respondents who were consistent in their judgments of the relevance of the criteria and their preferences for the screening techniques. The most preferred screening method for the national screening program was CT colonography. Sensitivity (weightxa0=xa00.26) and safety (weightxa0=xa00.26) were the strongest determinants of the overall preferences for the screening techniques. However, the screening test with the highest intention to attend was iFOBT. Inconvenience (correlation [r]xa0=xa00.69), safety (rxa0=xa00.58), and the frequency of the test (rxa0=xa00.58) were most strongly related to intention to attend.ConclusionsThe multi-criteria decision analysis revealed the attributes of the screening techniques that are most important so as to increase intention to participate in a screening program. Even though the respondents may recognize the high importance of diagnostic effectiveness in the long term, their short-term decision to attend the screening tests may be less driven by this consideration. Our analysis suggests that inconvenience, safety, and frequency of the test are the strongest technique-related determinants of the respondents’ intention to participate in colorectal screening programs.

Public stated preferences and predicted uptake for genome-based colorectal cancer screening

BackgroundEmerging developments in nanomedicine allow the development of genome-based technologies for non-invasive and individualised screening for diseases such as colorectal cancer. The main objective of this study was to measure user preferences for colorectal cancer screening using a nanopill.MethodsA discrete choice experiment was used to estimate the preferences for five competing diagnostic techniques including the nanopill and iFOBT. Alternative screening scenarios were described using five attributes namely: preparation involved, sensitivity, specificity, complication rate and testing frequency. Fourteen random and two fixed choice tasks, each consisting of three alternatives, were offered to 2225 individuals. Data were analysed using the McFadden conditional logit model.ResultsThirteen hundred and fifty-six respondents completed the questionnaire. The most important attributes (and preferred levels) were the screening technique (nanopill), sensitivity (100%) and preparation (no preparation). Stated screening uptake for the nanopill was 79%, compared to 76% for iFOBT. In the case of screening with the nanopill, the percentage of people preferring not to be screened would be reduced from 19.2% (iFOBT) to 16.7%.ConclusionsAlthough the expected benefits of nanotechnology based colorectal cancer screening are improved screening uptake, assuming more accurate test results and less preparation involved, the relative preference of the nanopill is only slightly higher than the iFOBT. Estimating user preferences during the development of diagnostic technologies could be used to identify relative performance, including perceived benefits and harms compared to competitors allowing for significant changes to be made throughout the process of development.

A randomised cross-over trial investigating the ease of use and preference of two dry powder inhalers in patients with asthma ofr chronic obstructive pulmonary disease

Objectives: The objective of this randomised, cross-over study was to compare a new single-dose dry powder inhaler (Elpenhaler (EH)), with a widely used, multi-dose dry powder inhaler (Diskus (DK)) on critical errors, patient preference, and satisfaction with the inhalers. Methods: First, patients read the instructions of one device, followed by a first inhalation attempt. Inhalation errors were assessed and if mistakes were made, correct inhaler use was demonstrated. Then patients had to demonstrate again and mistakes were registered. This was repeated up to four times. After completing the first device, the same procedure was started with the second inhaler. Primary outcome was the percentage of patients making at least one critical error after reading the insert. Secondary outcomes were inhaler preference and satisfaction with the inhalers. Results: After reading the insert, 19 of 113 patients (17%) made at least one critical error with DK and 40 (35%) with EH (p = 0.001); 73% preferred the DK and 27% the EH (p < 0.001). The mean overall satisfaction score (1 = very satisfied; 5 = very dissatisfied) for DK was 1.59 and for EH 2.48 (p < 0.001). Conclusion: With DK fewer errors were made, more patients preferred DK over EH and patients were more satisfied with DK. This may enable DK to improve treatment outcomes more than EH.

Words or graphics to present a Discrete Choice Experiment: Does it matter?

OBJECTIVEnTo test whether presenting attribute levels in words or graphics generates different results with respect to attribute level interpretation, relative importance and participation probabilities.nnnMETHODSnParents of 959 newborns completed a DCE questionnaire that contained two versions of the same nine choice tasks in which the attribute levels were presented in words or graphics. Five attributes related to the decision of parents to vaccinate their newborn against rotavirus were included. Mixed-logit models were conducted to estimate the relative importance of the attribute levels.nnnRESULTSnRespondents who started with the choice tasks in words produced the most consistent answer patterns. All respondents significantly preferred words to graphics. Part-worth utilities and the relative importance of the attribute levels differed based on the words and graphics data, resulting in different probabilities to participate in vaccination.nnnCONCLUSIONSnWords were preferred over graphics, resulted in higher choice consistency, and showed more valid attribute level estimates. Graphics did not improve respondents understanding of the attribute levels.nnnPRACTICE IMPLICATIONSnFuture research on the use of either words or graphics is recommended in order to establish guidelines on how to develop a valid presentation method for attribute levels in the choice tasks of a DCE.