Significant Differences In Estimates Research Articles

Comparison of methods for evaluating genetic differentiation of populations by microsatellite markers

Comparative studies of eight methods for evaluation of genetic differences by microsatellite (STR) markers (11 loci) DNA were carried out using the example of seven breed samples (N = 84) of dairy cattle. The range of indicators of genetic diversity of samples was as follows: the number of alleles per locus 3.5-6.2, the number of effective alleles per locus – 2.4-4.3, the Shannon index – 0.95-1.56, the observed and expected heterozygosity – 0.56-0.97 and 0.53-0.75. Evaluation summary of genetic differentiation by group A methods (FST, GST, and GST(NEI)) were 13.4, 10.3, and 11.8% (pperm < 0.001); the differences between the estimates were statistically insignificant. Estimates by group B methods (G'ST(HED), G''ST(HED), DEST) were 36.4, 37.5 and 29.2% (pperm < 0.001); differences between the estimates were also statistically insignificant. Estimates obtained by group B methods were statistically significantly higher than those obtained by group A methods by almost 3 times. Methods of groups A, B, and C (GDN and uGDN) were used to calculate paired genetic distances in the samples. Despite significant dif-ferences in estimates, the Mantel test showed a high degree of correspondence of the genetic distance matrices (RM≥0.97; pperm < 0.001), which was manifested in the projections of genetic relations of breed samples on plane 1 and 2 of the principal coordinates. The first two principal coordinates explained 97-99% of STR variation in the genetic distance matrices. It can be assumed that when assessing the actual differentiation of populations by STR-markers, the methods of group B should be used and among them the statistics of DEST as independent of the level of mean within-subpopulation heterozygosity. In the study of spatial ordination of gene pools of populations, in all probability, it is reasonably to use any method.

Forcing you to experience wonder: Unconsciously biasing people's choice through strategic physical positioning.

Magicians have developed powerful tools to covertly force a spectator to choose a specific card. We investigate the physical location force, in which four cards (from left to right: 1-2-3-4) are placed face-down on the table in a line, after which participants are asked to push out one card. The force is thought to rely on a behavioural bias in that people are more likely to choose the third card from their left. Participants felt that their choice was extremely free, yet 60% selected the 3rd card. There was no significant difference in estimates and feelings of freedom between those who chose the target card (i.e. 3rd card) and those who selected a different card, and they underestimated the actual proportion of people who selected the target card. These results illustrate that participants' behaviour was heavily biased towards choosing the third card, but were oblivious to this bias.

Evaluating multispecies survey designs using a joint species distribution model

Survey designs should be efficient as marine survey programs are usually expensive and time-consuming; however, surveys have rarely been evaluated for multiple species. In the present study, we evaluated multispecies fisheries surveys with respect to three influential factors, i.e., sampling methods, estimation methods and sample size. A joint species distribution model (JSDM) developed in north Yellow Sea, China was used as the operating model to simulate the spatial distribution of multiple species simultaneously. We examined the precision of multispecies abundance estimation using diverse sampling methods [random sampling (RDS), systematic sampling (SYS), stratified random sampling (SRS), generalized random-tessellation stratified sampling (GRT) and spatial coverage sampling (SPC)], estimation methods [arithmetic mean (Arm), universal kriging (Ukr), multivariate distribution model (Mvd), and boral model (Brm)], and a range of sample sizes (from 30 to 300). The results showed significant differences in estimation among sampling methods, where GRT and SYS yielded less relative absolute bias (RAB) over all and RDS showed the least precision. Regarding estimation methods, Mvd and Arm showed the best performances and Brm yielded the least precision. Significant interactions existed between sampling and estimation methods. Arm worked best with GRT, likewise Mvd with SYS and Ukr with SPC. SPC and Mvd showed the best performances for a small sample size (N = 30), and all sampling and estimation methods provided similar results for a large sample size (N = 300). Generally, doubling sample size resulted in a decrease of RAB by 0.097 on average, a rate depending on species, sampling and estimation methods. This study contributed to an integrative framework for evaluating designs of multispecies fisheries surveys.

Development and application of a low-cost rapid assessment system for coastal benthic habitats.

Information on community structure and spatial distribution of benthic habitats are important in marine conservation and management. Coral areas, often monitored by trained scuba divers, are of importance for the ecosystem goods and services they provide. The data gathered may, however, be limited due to cost and time constraints. These restrictions and the continuing decline in coral reef health contribute to the need to develop rapid methods to efficiently document the distribution and status of coral reefs. A Rapid Assessment Instrument for Coastal Benthic Habitats (ARAICoBeH) System was developed to enable large-scale but low-cost coastal benthic habitat characterization and mapping without compromising accuracy. Inquiries on community structure and status in coral-dominated areas are also possible with the data collected using the method. The instrument, as well as the data processing and mapping algorithm are described in detail in this paper. A comparative study was conducted between ARAICoBeH and the frequently used underwater photo transect method. Variables compared were percent coral cover, functional group diversity, community structure as well as time and monetary requirements. There were no significant differences in estimates of percent coral cover and diversity of benthic functional groups for majority of sites while estimates of community structure were very similar. ARAICoBeH is cheaper and requires less time to gather the same amount of data as that of the photo transect method. The spatial distribution of coastal benthic habitats and community structure of coral-dominated areas in El Nido, Palawan, Philippines, are included to illustrate the application of the method.

PC082. High-Granularity Geographic Information System Analysis of Amputation Trends in West Virginia Identifies Specific Geographic Areas to Target for Improved Diabetes and Peripheral Artery Disease Care

Amputation is a devastating but preventable complication of diabetes and peripheral artery disease (PAD). Multiple studies have focused on disparities in amputation rates based on race/ethnicity and socioeconomic status, but few focus on amputation trends in rural populations. This study’s objective was to identify the prevalence of major and minor amputation among those with documented disease in a rural Appalachian state and to use advanced spatial epidemiology methods to identify high-risk areas for amputation. This study used 2011 to 2016 hospital discharge data from the West Virginia State Inpatient Database to identify all adults (>18 years) with recorded diagnoses of diabetes or PAD. Major and minor amputations in this population were identified using International Classification of Diseases, Ninth Revision and Tenth Revision codes. Amputation rate was defined as the number of amputations among admissions with diabetes or PAD. To identify high-risk areas for amputation, Bayesian spatial hierarchical modeling was conducted to obtain model-fitted relative risk estimates at both the county and ZIP code level (of patient residence), and the deviance information criterion was used to investigate model performance. In 2011 to 2016, there were 519,990 admissions that met the criteria of diabetes or PAD. Among them, 2584 major and 3829 minor amputations were performed, with 6279 amputations performed overall, corresponding to a rate of 12.1/1000. This number is significantly higher than the national average of 2.4/1000 reported in other studies. On geographic analysis, we found significant variation in risk for both major and minor amputation across the state, even after adjusting for the prevalence of risk factors. Specifically, we found that ZIP codes in central and northeastern West Virginia had relative risks of amputation >1.5 times higher than the rest of the state (Figs 1 and 2). In addition, we found significant differences in estimates between standard crude risk estimation for this disease and our method, which was able to illustrate amputation risk at a much higher level of granularity by producing ZIP code-level data on amputation risk while controlling for associated comorbidities. We found a significantly higher prevalence of amputation in West Virginia compared with the national prevalence reported in other studies. In addition, we found significant geographic variation in amputation risk across the state and identified highly specific areas where, even after adjusting for covariates, the risk of amputation among those with diabetes or PAD was higher than expected. These findings allow the targeted allocation of resources for amputation prevention efforts and also direct further research to gain a greater understanding of the cause of this issue.Fig 2Geographic variation in model-fitted estimates of ZIP code-level relative risk of minor amputation in West Virginia, 2011 to 2016.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

COMPARATIVE ANALYSIS OF THE CONTRIBUTION OF SHORT-LIVED RADIOIODINES TO THE THYROID RADIATION DOSE FOR THE POPULATION AFTER THE CHERNOBYL AND FUKUSHIMA ACCIDENTS

Purpose. To present results of the comparative analysis of the contribution of short-lived radioiodines to the thyroid radiation dose (TRD) in the population after two severe radiation accidents at nuclear reactors: the Chernobyl accident (1986) and the Fukushima accident (2011). Material and methods. The contribution of short-lived radioiodines to the TRD is expressed in fractions of the TRD from 131I (the main dose forming radionuclide). This contribution takes into account the ratio between doses from inhalation and ingestion intake of 131I, the ratios between dose factors of the expected dose to the thyroid gland in the case of inhalation and ingestion intake of iodine and tellurium isotopes, the ratios between time-integrated concentration of iodine and tellurium isotopes at the ground-level air and in foodstuffs (milk). Results. The typical contribution of short-lived radioiodines to TRD for the population accounts of few percent of dose to the thyroid gland from 131I following the Chernobyl accident as on March 15, 2011, the day of the main fallout after the Fukushima accident - within 15%. For both accidents the leading role among the short-lived radioiodines in terms of dose to the thyroid for the public belongs to 133I and 132I (due to the intake of 132Te and its radioactive decay to 132I in the body). Conclusion. Significant differences in estimates of the typical contribution of short-lived radioiodines to TRD for the population after two considered accidents can be explained by differences in the dominant pathways of the intake of radioiodine by population. The dominant pathway for the vast majority of the population in the contaminated areas following the Chernobyl accident was ingestion intake with locally produced cow’s milk. Following the Fukushima accident the dominant pathway was inhalation intake, because the Japanese authorities were able to quickly prevent the intake of radioiodine with foodstuffs.

Antihypertensive Agents in Older Adults: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.

This systematic review summarizes the benefits of treating blood pressure (BP) in individuals 65 years and older. We included randomized trials that evaluated BP-lowering medications or BP targets in individuals 65 years and older. Trials were selected and appraised by pairs of independent reviewers. We included 19 trials (42,134 patients). In individuals 65 years or older, antihypertensive therapy was associated with a reduction in all-cause mortality [relative risk: 0.88 (95% CI: 0.81 to 0.94); high certainty evidence; mean follow-up 31 months], cardiovascular mortality, myocardial infarction, heart failure, stroke, and chronic kidney disease. Individuals 75 years or older had a significant reduction in the risk of all-cause and cardiovascular mortality, stroke, and heart failure. Strict systolic BP targets (<120 mm Hg and <130 mm Hg) were associated with a significant reduction in the risk of all-cause and cardiovascular mortality and heart failure, whereas more liberal systolic targets (<150 mm Hg and <160 mm Hg) were associated with lower risk of heart failure and stroke. Older adults with type 2 diabetes mellitus (DM) had lower risk of chronic kidney disease without a significant reduction in other outcomes. However, there was no significant difference in estimates (i.e., interaction) between those with and without DM. Individuals aged 65 years and older or 75 years and older who receive antihypertensive therapy have statistically significant reduction in the risk of all-cause and cardiovascular mortality, heart failure, and stroke. There was no statistically significant difference in estimates between those with and without DM.

Vision-Based Heart and Respiratory Rate Monitoring During Sleep - A Validation Study for the Population at Risk of Sleep Apnea.

A reliable, accessible, and non-intrusive method for tracking respiratory and heart rate is important for improving monitoring and detection of sleep apnea. In this study, an algorithm based on motion analysis of infrared video recordings was validated in 50 adults referred for clinical overnight polysomnography (PSG). The algorithm tracks the displacements of selected feature points on each sleeping participant and extracts respiratory rate using principal component analysis and heart rate using independent component analysis. For respiratory rate estimation (mean ± standard deviation), 89.89 % ± 10.95 % of the overnight estimation was accurate within 1 breath per minute compared to the PSG-derived respiratory rate from the respiratory inductive plethysmography signal, with an average root mean square error (RMSE) of 2.10 ± 1.64 breaths per minute. For heart rate estimation, 77.97 % ± 18.91 % of the overnight estimation was within 5 beats per minute of the heart rate derived from the pulse oximetry signal from PSG, with mean RMSE of 7.47 ± 4.79 beats per minute. No significant difference in estimation of RMSE of either signal was found according to differences in body position, sleep stage, or amount of the body covered by blankets. This vision-based method may prove suitable for overnight, non-contact monitoring of respiratory rate. However, at present, heart rate monitoring is less reliable and will require further work to improve accuracy.

Quality control limits: Are we setting them too wide?

BackgroundQuality control charts (Levey Jennings Charts) are based on estimates of variation. There are two general approaches for estimating variation: those based on short-term variation and those based on long-term variation. We have observed that clinical laboratory science (CLS) tends to estimate variation using long-term variation but that most other fields use short-term variation. The objective of this study is to compare these two methods of estimating process variation, compare the accuracy of control limits generated by each method, and explore whether it would be useful for clinical laboratories to adopt methods used in other fields. MethodsWe conducted a literature review to compare recommendations for methods for estimation of variation in CLS with other fields. We searched textbooks for suggested methods and also searched the primary literature for references to methods associated with short-term and long-term variation. We provide theoretical results from statistics to show that, in theory, short-term estimates can differ from long-term estimates of variation. We used simulation studies to show that one can construct examples where short-term and long-term estimates of variation lead to significant differences in control limits. Finally, we show laboratory data comparing short-term and long-term estimates of variation. ResultsWe found that practice in CLS differs from other fields. We found no references to methods based on short-term variation in CLS textbooks and only one reference in the primary literature. In contrast, standard quality control (QC) texts recommend methods based on short-term variation and the primary literature makes frequent reference to such methods. We found statistical papers that show that, in theory, estimates based on long-term variation can produce inflated estimates of process variation. We used simulation to show that such examples can be constructed. We examined 95 QC charts and found that in 93 cases, there were significant differences between short-term and long-term estimates of variation. The ratio of long-term to short-term variation was greater than 1.5 in 18% of cases. ConclusionEstimates of variation based on short-term and long-term variation can lead to significant differences in estimates. Estimates based on long-term variation are frequently larger than estimates based on short-term variation.

Medicare Accountable Care Organization Enrollment and Appropriateness of Cancer Screening

ImportanceDespite rapid diffusion of Accountable Care Organizations (ACOs), whether ACO enrollment results in observable changes in cancer screening remains unknown.ObjectiveTo determine whether Medicare Shared Savings Program (MSSP) ACO enrollment changes the appropriateness of screening for breast, colorectal, and prostate cancers.Design, Setting, and ParticipantsFor this population-based analysis of Medicare beneficiaries, we used Medicare data from 2007 through 2014 and evaluated changes in screening associated with ACO enrollment using differences-in-differences (DD) analyses. We then performed difference-in-difference-in-differences (DDD) analyses to determine whether observed changes in cancer screening associated with ACO enrollment were different across strata of appropriateness, defined using age (65-74 years vs ≥75 years) and predicted survival (top vs bottom quartile).Main Outcomes and MeasuresRates of breast, colorectal, and prostate cancer screening measured yearly as a proportion of eligible Medicare beneficiaries undergoing relevant screening services.ResultsAmong Medicare beneficiaries, comprising 39 218 652 person-years before MSSP enrollment and 17 252 345 person-years after MSSP enrollment, breast cancer screening declined among both ACO (42.7% precontract, 38.1% postcontract) and non-ACO (37.3% precontract, 34.1% postcontract) populations. The adjusted rate of decline (DD) in the ACO population exceeded the non-ACO population by 0.79% (P < .001). This decline was most pronounced among elderly women (–2.1%), with minimal observed change among younger women (−0.26%). Baseline colorectal cancer screening rates were lower than those for breast cancer among both ACO (10.1% precontract, 10.3% postcontract) and non-ACO (9.2% precontract, 9.1% postcontract) populations. We observed an adjusted 0.24% (P = .03) increase in screening associated with ACO enrollment, most pronounced among younger Medicare beneficiaries (0.36%). For breast and colorectal cancer, we observed statistically significant differences in estimates of effect between age strata, suggesting that the ACO effect on cancer screening is mediated by age (DDD for both P < .001). Prostate cancer screening declined among ACO (35.1% precontract, 28.5% postcontract) and non-ACO (31.2% precontract, 25.7% postcontract) populations. The adjusted rate of decline in the ACO population exceeded that of the non-ACO population by 1.2%. We observed no difference in estimate of effect between age strata, suggesting that the ACO-mediated changes in prostate cancer screening are similar among younger and elderly men. Results characterizing appropriateness with predicted survival mirrored those when stratified by age.Conclusions and RelevanceMedicare Shared Savings Program ACO enrollment is associated with more appropriate breast and colorectal screening, although the magnitude of the observed ACO effect is modest in the early ACO experience.

Cost and performance tradeoffs between mail and internet survey modes in a nonmarket valuation study

Using the results of a choice modeling survey, internet, mail-only and mixed internet and mail survey modes were examined with regards to their cost-effectiveness, representativeness, and willingness to pay (WTP). The topical focus of the study was biomass energy generation preferences of the residents of Montana, Colorado and Arizona, USA. Compared to the mail and mixed mode samples, the internet-only mode produced a sample of respondents that was younger, more likely to have a college degree, and more likely to have a household income of at least $100,000 per year. However, observed differences in the characteristics of the collected sample did not result in significant differences in estimates of WTP. The internet survey mode was the most cost-effective method of collecting the target sample size of 400 responses. Sensitivity analysis showed that as the target number of responses increased the cost advantage of internet over the mail-only and mixed mode surveys increased because of the low marginal cost associated with extending additional invitations.

Development, validation and reproducibility of a food frequency questionnaire to measure flavonoid intake in older Australian adults.

To develop and assess the validity and reproducibility of a food frequency questionnaire (FFQ) to measure total flavonoid intake, and individual flavonoid subclasses, in older adults. Retrospective analysis of flavonoid intake in older adults informed the development of a FFQ to measure flavonoid intake and determine the flavonoid subclasses consumed (anthocyanins, flavan-3-ols, flavones, flavonols and flavanones). Older adults (n = 42, mean age 75.3 ± 8.6 years) attended two interviews 1 month apart where anthropometrics (height and weight), blood pressure (BP), demographic data and a 93-item self-administered FFQ were collected. A 4-day food record (FR) was randomly administered between the two interview dates, and each food item was assigned a flavonoid and flavonoid subclass content using the United States Department of Agriculture flavonoid database. The criterion validity and reproducibility of the FFQ was assessed against a 4-day FR using the Wilcoxon signed-rank sum test, Spearman's correlation coefficient (r), Bland-Altman Plots and Cohen's kappa. Total flavonoid intake was determined (median intake FFQ = 919.3 mg/day, FR = 781.4 mg/day). Tests of validity indicated that the FFQ consistently overestimated total flavonoid intake compared with the 4-day FR. There was a significant difference in estimates between the FFQ and the 4-day FR for total flavonoid intake (Wilcoxon signed-rank sum P < 0.001; Bland-Altman plots indicated large bias and wide limits of agreement), but they were well correlated (Spearman's r 0.93, P < 0.001; Cohen's kappa κ = 0.619, P < 0.001). For individual flavonoid subclasses, the tests of validity indicated greater discrepancy compared with 4-day FR. The FFQ showed high reproducibility for estimating total flavonoid intake (FFQ1vsFFQ2: Wilcoxon signed-rank sum test, P > 0.05; Spearman's r 0.91, P < 0.001; Bland-Altman plots visually showed small, non-significant bias and wide limits of agreement; and Cohen's kappa κ = 0.619, P < 0.001), with a small mean percentage difference (6.7%). For individual flavonoid subclasses, the tests of reproducibility between FFQ1 and FFQ2 showed similarly high reproducibility. The developed FFQ appears suitable for satisfactorily ranking individuals according to total flavonoid intake. The FFQ shows limitations for estimating absolute total flavonoid intake and intake of flavonoid subclasses in comparison to a 4-day FR in terms of overestimating intake. Refinement and further validation of this tool may be required.

Comparison of estimates of neuronal number obtained using the isotropic fractionator method and unbiased stereology in day old chicks (Gallus domesticus)

BackgroundThe relative size and neuronal density of brain regions are important metrics in both comparative and experimental studies in neuroscience. Consequently, it is imperative to have accurate, reliable and reproducible methods of quantifying cell number. New methodThe isotropic fractionator (IF) method estimates the number of neurons and non-neurons in the central nervous system by homogenizing tissue into discrete nuclei and determining the proportion of neurons from non-neurons using immunohistochemistry (Herculano- Herculano-Houzel and Lent, 2005). Comparison with existing methodOne of the advantages of IF is that it is considerably faster than stereology. However, as the method is relatively new, concerns about its accuracy remain, particularly whether homogenization results in underestimation of cell number. In this study, we compared estimates of neuronal number in the telencephalon and ‘rest of brain’ (i.e. the diencephalon and brainstem excluding the optic lobes) of day old chicks using the IF method and stereology. ResultsIn the telencephalon, there was a significant difference in estimates of neuronal number between the 2 methods, but not estimates of neuronal density (neurons/mg of tissue). Whereas in the ‘rest of brain’, there was a significant difference in estimates of neuronal density, but not neuronal number. In all cases, stereological estimates were lower than those obtained using the IF method. ConclusionDespite the statistically significant differences, there was considerable overlap (all estimates were within 16% of one another) between estimates obtained using the two methods suggesting that the two methods provide comparable estimates of neuronal number in birds.

How do medical students use and understand pain rating scales?

Background and aimsPain is a multidimensional experience that is difficult to describe and to assess. To scale current pain, assessment refers to a maximum level of pain, but little is known about this process. Further, clinicians tend to underestimate patients’ pain, with or without patients’ own reports, and to underestimate to a greater extent with more clinical experience, possibly due to recalibration of a personal pain scale with increasing exposure to severe pain. We sought to determine how medical students rated pain in early years of clinical exposure, and in relation to experience of their own and others’ worst pains. MethodsAn online survey sampled medical students’ rating and description of their own worst pain and of that witnessed in another; also what would cause the maximum level of pain and what behaviours characterised it. Last, they indicated their preference among pain scales. ResultsThirty-six medical students provided responses, the majority in their first six months of clinical exposure. Students’ own worst pain was rated a mean of 6.7/10 (s.d. 1.6) on a numerical scale; causes were diverse but with many bone fractures. Mean worst pain observed in another was rated 8.6/10 (s.d. 1.4); causes included fractures, gallstones, and sickle cell crises. Another's worst pain was significantly higher (mean 9.4, s.d. 0.8 vs mean 8.0 s.d. 1.4) when rated after the student's own pain than before it (presentation order randomised).We found no effect of clinical exposure on estimation of worst pain in another person, nor was there a personal tendency to rate pain using more or less extreme values. Students expected pain of 10/10 to be presented with many verbal, facial and whole body behaviours, and signs of physiological stress. Collectively, behavioural descriptions were rich and varied, but with many incompatibilities: for instance, between ‘writhing’ and ‘rigidity’ expected in the person with extreme pain. Most students preferred the numerical rating scale over visual analogue and verbal scales. ConclusionsThe study requires replication, particularly for clinical experience, where we found no significant difference in estimation of another's pain over the first three years of medical students’ clinical exposure, but the comparison was underpowered. Despite no systematic individual difference in using pain ratings, there was a marked effect of rating another's worst pain higher when the rater had previously rated his/her own worst pain. This suggests anchoring estimate of another's pain in personal pain experience, and a possible way to mitigate clinicians’ underestimation of patients’ pain.Medical students’ recognition of the importance of facial expression in indicating another's pain severity was encouraging, but most students anticipated only a narrow range of behaviours associated with extreme pain, thereby excluding other authentic behaviours. ImplicationsMany clinical guidelines mandate regular pain assessment for hospital inpatients, and encourage routine assessment in community and outpatient settings, in order to decide on and monitor treatment. Replication and elaboration of this study could extend our understanding of how clinicians interpret pain scales completed by patients, and how they estimate patients’ pain.

The Effect of Hindsight Bias on Psychiatrists’ Clinical Judgment: A Randomized Controlled Trials

Abstract Objectives: Hindsight bias is inevitable in retrospective peer reviews, especially in medical settings. Psychiatrists are highly at risk of hindsight bias, because of the repeated patient hospitalization and the use of medications with a lot of side effects. The goal of our study was to investigate the effect of hindsight bias on psychiatrists’ clinical judgment. Methods: We conducted our survey in 173 psychiatrists who participated in the congress of scientific society of psychiatrists in Iran in December 2010. A clinical vignette was presented to participants and they reviewed hypothetical cases in which patients with bipolar or psychotic features presented for psychiatric care. We informed two-thirds of the participants that a bipolar or psychotic feature accompanied patients’ symptoms (hindsight group) but withheld outcome information from the other participants (control group). Participants were asked to estimate the likelihood of each differential diagnosis. Results: Responses were compared between groups for suggestions of hindsight bias. The results indicate that hindsight bias plays a role in overestimating likelihood of psychotic disorder in these three groups (P value<0.05). Post-hoc analysis confirmed that this difference arises from difference in perceived probability of psychotic disorder without a significant difference in estimation of likelihood of mood disorder. Conclusion: Psychiatry just like other specialties is vulnerable to hindsight bias and its consequences, such as inappropriate treatments and unnecessary hospital admissions. Our results indicate that psychiatrist who was informed with psychotic disorders, which its misdiagnosis would result in more adverse outcome, would be more prone to hindsight bias.

Weighting Strategies for Combining Data from Dual-Frame Telephone Surveys: Emerging Evidence from Australia

Abstract Until quite recently, telephone surveys have typically relied on landline telephone numbers. However, with the increasing popularity and affordability of mobile phones, there has been a surge in households that do not have landline connections. Additionally, there has been a decline in the response rates and population coverage of landline telephone surveys, creating a challenge to collecting representative social data. Dual-frame telephone surveys that use both landline and mobile phone sampling frames can overcome the incompleteness of landline-only telephone sampling. However, surveying mobile phone users introduces new complexities in sampling, nonresponse measurement and statistical weighting. This article examines these issues and illustrates the consequences of failing to include mobile-phone-only users in telephone surveys using data from Australia. Results show that there are significant differences in estimates of populations’ characteristics when using information solely from the landline or mobile telephone sample. These biases in the population estimates are significantly reduced when data from the mobile and landline samples are combined and appropriate dual-frame survey estimators are used. The optimal choice of a dual-frame estimation strategy depends on the availability of good-quality information that can account for the differential patterns of nonresponse by frame.

Validation of a Side‐Scan Sonar Method for Quantifying Walleye Spawning Habitat Availability in the Littoral Zone of Northern Wisconsin Lakes

AbstractPrevious research has generally ignored the potential effects of spawning habitat availability and quality on recruitment of Walleye Sander vitreus, largely because information on spawning habitat is lacking for many lakes. Furthermore, traditional transect‐based methods used to describe habitat are time and labor intensive. Our objectives were to determine if side‐scan sonar could be used to accurately classify Walleye spawning habitat in the nearshore littoral zone and provide lakewide estimates of spawning habitat availability similar to estimates obtained from a transect–quadrat‐based method. Based on assessments completed on 16 northern Wisconsin lakes, interpretation of side‐scan sonar images resulted in correct identification of substrate size‐class for 93% (177 of 191) of selected locations and all incorrect classifications were within ± 1 class of the correct substrate size‐class. Gravel, cobble, and rubble substrates were incorrectly identified from side‐scan images in only two instances (1% misclassification), suggesting that side‐scan sonar can be used to accurately identify preferred Walleye spawning substrates. Additionally, we detected no significant differences in estimates of lakewide littoral zone substrate compositions estimated using side‐scan sonar and a traditional transect–quadrat‐based method. Our results indicate that side‐scan sonar offers a practical, accurate, and efficient technique for assessing substrate composition and quantifying potential Walleye spawning habitat in the nearshore littoral zone of north temperate lakes.Received December 1, 2015; accepted March 24, 2016 Published online July 20, 2016

Mapping and Characterization of Hydrological Dynamics in a Coastal Marsh Using High Temporal Resolution Sentinel-1A Images

In Europe, water levels in wetlands are widely controlled by environmental managers and farmers. However, the influence of these management practices on hydrodynamics and biodiversity remains poorly understood. This study assesses advantages of using radar data from the recently launched Sentinel-1A satellite to monitor hydrological dynamics of the Poitevin marshland in western France. We analyze a time series of 14 radar images acquired in VV and HV polarizations from December 2014 to May 2015 with a 12-day time step. Both polarizations are used with a hysteresis thresholding algorithm which uses both spatial and temporal information to distinguish open water, flooded vegetation and non-flooded grassland. Classification results are compared to in situ piezometric measurements combined with a Digital Terrain Model derived from LiDAR data. Results reveal that open water is successfully detected, whereas flooded grasslands with emergent vegetation and fine-grained patterns are detected with moderate accuracy. Five hydrological regimes are derived from the flood duration and mapped. Analysis of time steps in the time series shows that decreased temporal repetitivity induces significant differences in estimates of flood duration. These results illustrate the great potential to monitor variations in seasonal floods with the high temporal frequency of Sentinel-1A acquisitions.

Cross-cultural variation in preference for replantation or revision amputation: Societal and surgeon views

Treatment decisions after an injury like finger amputation are made based on injury and patient factors. However, decisions can also be influenced by provider and patient preferences. We compared hand surgeon and societal preferences and attitudes regarding finger amputation treatment in Japan and the US. We performed a cross-sectional survey with subjects derived from large tertiary care academic institutions in the US and Japan. We secured 100% participation of American hand surgeon members of the Finger Replantation and Amputation Multicenter Study and presenting hand surgeons at the 32nd Annual meeting of the Central Japanese Society for Surgery of the Hand. Societal preferences were gathered from volunteers at the 2 universities in the US and Japan. There were no significant differences in estimations of function, sensation, or appearance after replantation; American and Japanese societal participants preferred replantation compared to surgeons, although this was more pronounced in Japan. The Japanese society displayed more negative attitudes toward finger amputees than did Japanese surgeons. American respondents anticipated more public stigmatisation of amputees than did American surgeons. Societal preference for replantation was not caused by inflated expectations of outcomes after replantation. Japanese societal preference was likely driven by negative views of finger amputees. American society noted no decrease in physical health after amputation, but did note a quality of life decrease attributed to public stigmatisation. Japanese society and surgeons had a stronger preference for replantation than American society and surgeons, possibly attributed to cultural differences.

The Beta Heuristic from a Time/Frequency Perspective: A Wavelet Analysis of the Market Risk of the 10 S&amp;P Sectors

We investigate the time-scale relationships between the ten S&P sectors and the market through the use of wavelet analysis, a methodology that has widespread acceptance for investigating multi-horizon properties of time series. Our analysis of the data highlights that variation in the pattern of dependency among sector returns and market returns, even at times of market turmoil, appears differently at different time horizons and frequency intervals. The empirical evidence based on standard betas and scale betas finds that the flow of frequency changes matters for estimates of market betas at medium and higher scales for nine out of ten sectors. There are no significant differences in estimates of scale market betas at high frequency for any of the sectors, or at any scales for the energy sector. We conclude that the importance of frequency components does not remain stable over time and based on the effects of time-varying behavior at different frequencies draw implications for investors regarding the market risk of investing in specific sectors.