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Mutations in PRRT2 are not a common cause of infantile epileptic encephalopathies
No full textHeterozygous mutations in PRRT2 have recently been identified as the major cause of autosomal dominant benign familial infantile epilepsy (BFIE), infantile convulsions with choreoathetosis syndrome (ICCA), and paroxysmal kinesigenic dyskinesia (PKD). Homozygous mutations in PRRT2 have also been reported in two families with intellectual disability (ID) and seizures. Heterozygous mutations in the genes KCNQ2 and SCN2A cause the two other autosomal dominant seizure disorders of infancy: benign familial neonatal epilepsy and benign familial neonatal-infantile epilepsy. Mutations in KCNQ2 and SCN2A also contribute to severe infantile epileptic encephalopathies (IEEs) in which seizures and intellectual disability co-occur. We therefore hypothesized that PRRT2 mutations may also underlie cases of IEE. We examined PRRT2 for heterozygous, compound heterozygous or homozygous mutations to determine their frequency in causing epileptic encephalopathies (EEs). Two hundred twenty patients with EEs with onset by 2 years were phenotyped. An assay for the common PRRT2 c.649-650insC mutation and high resolution-melt analysis for mutations in the remaining exons of PRRT2 were performed. Neither the common mutation nor any other pathogenic variants in PRRT2 were detected in the 220 patients. Our findings suggest that mutations in PRRT2 are not a common cause of IEEs.
A comparison of importance weights and willingness-to-pay measures derived from choice-based conjoint, constant sum scales and best–worst scaling
No full textWe review the measurement of product attribute importance, and find little consensus in definition or measurement methods. We compare four measurement methods: 1) two direct methods whereby respondents report the importance of attributes using best–worst scaling or constant sum scales, and 2) two indirect methods derived from discrete choice experiments. Our comparisons rely on previous findings that choice experiments are externally valid to use as the standard. We find high agreement within direct or indirect methods, but less agreement between direct and indirect methods. Our results also demonstrate that inferences derived from indirect measures appear to be susceptible to context effects related to the particular attributes a researcher chooses to investigate. We discuss implications for current and future research.
Probabilistic models of set-dependent and attribute-level best-worst choice
No full textWe characterize a class of probabilistic choice models where the choice probabilities depend on two scales, one with a value for each available option and the other with a value for the set of available options. Then, we develop similar results for a task in which a person is presented with a profile of attributes, each at a pre-specified level, and chooses the best or the best and the worst of those attribute-levels. The latter design is an important variant on previous designs using best–worst choice to elicit preference information, and there is various evidence that it yields reliable interpretable data. Nonetheless, the data from a single such task cannot yield separate measures of the “importance” of an attribute and the “utility” of an attribute-level. We discuss various empirical designs, involving more than one task of the above general type, that may allow such separation of importance and utility.
Investment decisions for retirement savings
No full textWe conducted a choice experiment to investigate whether retirement savers follow simple portfolio theory when choosing investments. We modeled experimental survey data on 693 participants using a scale-adjusted version of the latent class choice model. Results show that underlying variability in response was explained by age and “risk profile” score and that preferences varied with income and age. Younger individuals were conventionally risk averse, but older, higher-income individuals may react positively to both higher returns and increasing risk, when risk is presented as widening ranges of possible outcomes. Respondents tended to choose among a few similar investment options.
Using best-worst scaling choice experiments to measure public perceptions and preferences for healthcare reform in Australia
No full textConclusions: This research demonstrates how random-utility-based methods can be used to provide estimates of the importance of reform principles that have known statistical properties. The BWS task used forced respondents to discriminate between the principles on offer, unlike rating scales. Researchers and practitioners in healthcare should consider using BWS tasks in preference to rating scales.
Information accessibility and consumers' knowledge of prescription drug benefits and risks
No full textBy increasing the visual accessibility of information in prescription drug advertisements, mechanical features enhance consumers' knowledge and attitudes, and increase the likelihood they will respond to the advertisement. An experiment using a print advertisement stimulus found that a “traffic light” heuristic elicited higher recall of both risks and benefits. These findings were partially replicated in an online study, where the “traffic light” was consistently more effective than the format currently used in New Zealand direct-to-consumer advertising. Simple measures that improve the visual accessibility of risk information support consumers' decision making and may also enable them to play more active roles in managing their health care.
Rationalisation as delusion : pictorial health warnings and tobacco industry arguments
No full textOriginality/value: This is the first comparison of pictorial and refreshed text warnings; the findings challenge the tobacco industry's position on tobacco warning labels and contradict arguments used to oppose the introduction of pictorial warning labels.