Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pretesting”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources
PubMed1998

How a regression artifact makes ICFs/MR look ineffective.

Based on a simple matched-control group quasi-experiment, Conroy (1996) concluded that small ICFs for persons with mental retardation have negative quality-of-life impacts. Our analysis of Conroy's design suggests, in contrast, that the reported effect is a pure regression artifact. The flaw in Conroy's design is selecting a control group on the basis of pretest matching. Although selecting a subsample of controls by matching on static characteristics such as age or gender can reduce the confounding influence of these variables, selection on the basis of pretest scores leads invariably to a large, spurious effect. The literature on this issue dates back a century, with warnings against pretest matching by Galton, Thorndike, McNemar, Stanley, Campbell, Cronbach, and Cook. We reviewed this historical literature and then used a Monte Carlo experiment to estimate the spurious effect that Conroy would observe from pretest matching alone. The magnitude of the artifact is as large as the quality-of-life reduction that Conroy attributed to the effects of living in an ICF. We discussed the methodological logic involved in matching and the broader policy issues raised by this evaluation.

Artifacts↗
PubMed1993

Diagnostic value of the bronchial provocation test with methacholine in asthma. A Bayesian analysis approach.

The Bayesian analysis was used in this study to investigate the diagnostic value of the bronchial provocation test with methacholine in patients with asthma. The best cutoff value of accumulated concentration of methacholine administered that caused a 20 percent fall in FEV1 post-saline (PC20) in our sample, determined with a receiver operator characteristic curve, was 15 mg/ml. The interval security of the test was established by a pretest probability between 0.16 and 0.87 and the best test results were obtained when pretest probability was 0.48. The positive final diagnostic gain of the test was maximal at this pretest probability. We conclude that the application of Bayes' theorem, considering the pretest probability of asthma and the sensitivity and specificity of the individual PC20 obtained, increases the accuracy of the bronchial provocation test with methacholine in the diagnosis of asthma.

Adult↗
PubMed2005

Clinical gestalt and the diagnosis of pulmonary embolism: does experience matter?

STUDY OBJECTIVES: We sought to determine whether the accuracy of pretest assessment of the likelihood of pulmonary embolism (PE) was related to physician experience. We compared the accuracy of the subjective pretest probability assessment made by senior physicians (postgraduate year [PGY]-4+) to that of interns (PGY-1) and residents (PGY-2 and PGY-3) working in the emergency department of a large teaching hospital. DESIGN: Prospective observational study. SETTING: Urban, academic emergency department with an annual census of 48,000 patient visits. PATIENTS: Five hundred eighty-three adults evaluated for PE in the emergency department. INTERVENTIONS: Eligible patients had at least one diagnostic test ordered to workup PE. The physician treating the patient was asked whether he or she considered PE the most-likely diagnosis or whether an alternative diagnosis was most likely. This result was compared to the ultimate diagnosis. Physician experience was categorized by the number of years of training since medical school graduation. MEASUREMENTS AND RESULTS: There was a trend toward increasing accuracy with increasing experience, demonstrated by the frequency of true-positive assessments (17% vs 20% vs 25%), true-negative assessments (89% vs 94% vs 96%), and likelihood ratio (1.49 vs 2.34 vs 3.33), respectively. CONCLUSIONS: Accurate determination of the pretest probability of PE appears to increase with clinical experience. However, the difference in accuracy between inexperienced and experienced physicians is not sufficiently large to distinguish between the two when determining whether clinical gestalt or a clinical prediction rule should be used to determine the pretest probability of PE.

Adult↗
PubMed2006

The effects of stability ball training on spinal stability in sedentary individuals.

Stability ball training (SBT) is believed to improve spinal stability (SS) and could reduce the risk of back pain in sedentary individuals. The purpose of this study was to examine the effects of SBT on SS. Twenty sedentary individuals were randomly assigned to either an experimental group that performed SBT twice per week for 10 weeks or to a control group. Differences between groups were assessed by analysis of variance (ANOVA) with repeated measures. The experimental group improved significantly (p < 0.05) on the static back-endurance test from pretest (149.3 +/- 72.3 seconds) to posttest (194.6 +/- 56.7 seconds) and the side bridge test from pretest (45.4 +/- 39.4 seconds) to posttest (71.3 +/- 59.7 seconds). Back endurance for the control group did not change from pretest (123.4 +/- 64.9 seconds) to posttest (87.5 +/- 40.2 seconds), nor did the results of the side bridge test change for this group from pretest (41.8 +/- 26.4 seconds) to posttest (51.6 +/- 35.9 seconds). These findings illustrate that SBT may provide improvements in SS within this population. Practitioners might use SBT exercises where the position of the spine is maintained during the early phases of back-pain prevention programs. This type of programming might be beneficial to individuals who spend a good deal of time sitting (i.e., in corporate fitness programs) or for individuals who are prone to back pain and have been cleared to exercise. Also, the side bridge and static back endurance assessments may be good choices for measuring SS in field settings.

Adult↗
PubMed2001

Newborns with suspected occult spinal dysraphism: a cost-effectiveness analysis of diagnostic strategies.

OBJECTIVE: To assess the clinical and economic consequences of different diagnostic strategies in newborns with suspected occult spinal dysraphism. METHODS: A decision-analytic model was constructed to project the cost and health outcomes of magnetic resonance imaging (MRI), ultrasound (US), plain radiographs, and no imaging in newborns with suspected occult spinal dysraphism. Morbidity and mortality rates of early versus late diagnosis of dysraphism and the sensitivity and specificity of MRI, US, and plain radiographs were obtained from the literature. Cost estimates were obtained from a hospital cost accounting database and from the Medicaid fee schedule. RESULTS: We found that the choice of imaging strategy depends on the underlying risk of occult spinal dysraphism. In low-risk children with intergluteal dimple or newborns of diabetic mothers (pretest probability: 0.3%-0.34%), US was the most effective strategy with an incremental cost-effectiveness ratio of $55 100 per quality-adjusted life year gained. For children with lumbosacral dimples, who have a higher pretest probability of 3.8%, US was less costly and more effective than the other 3 strategies considered. In intermediate-risk newborns with low anorectal malformation (pretest probability: 27%), US was more effective and less costly than radiographs and no imaging. However, MRI was more effective than US at an incremental cost-effectiveness of $1000 per quality-adjusted life year gained. In the high-risk group that included high anorectal malformation, cloacal malformation, and exstrophy (pretest probability: 44%-46%), MRI was actually cost-saving when compared with the other diagnostic strategies. For the intermediate-risk group, we found our analysis to be sensitive to the costs and diagnostic performances (sensitivity and specificity) of MRI and US. Lower MRI cost or greater MRI diagnostic performance improved the cost-effectiveness of the MRI strategy, whereas lower US cost or greater US diagnostic performance worsened the cost-effectiveness of the MRI strategy. Therefore, individual or institutional expertise with a specific diagnostic modality (MRI versus US) may influence the optimal diagnostic strategy. CONCLUSIONS: In newborns with suspected occult dysraphism, appropriate selection of patients and diagnostic strategy may increase quality-adjusted life expectancy and decrease cost of medical work-up.

Cost-Benefit Analysis↗
PubMed1987

Field replication of classwide peer tutoring.

We conducted a large-scale field replication study of classwide peer tutoring applied to spelling instruction (Greenwood, Delquadri, & Hall, 1984). Two hundred and eleven inner-city students in four schools participated during their first- and second-grade school years. The effects of classwide peer tutoring were compared to teacher instructional procedures and pretest probes using a group replication design (Barlow, Hayes, & Nelson, 1984). Analysis of group and individual results indicated that (a) both teacher instructional procedures and classwide peer tutoring were effective in increasing spelling performance above pretest levels, (b) peer tutoring produced statistically greater gains relative to the teachers' procedures for both low and high student groups formed on pretest levels, (c) these outcomes were representative of groups, classes, individuals, and years during the project, and (d) participant satisfaction with the program was generally high. A separate analysis of the social importance of treatment outcome revealed differential findings for low and high groups related to pretest levels. Implications of these findings are discussed.

Achievement↗
PubMedDate not supplied

Postexposure chemoprophylaxis for occupational exposure to human immunodeficiency virus in traveling health care workers.

BACKGROUND: There has been little research on the use of human immunodeficiency virus (HIV) postexposure prophylaxis (PEP) for occupational exposure in traveling health care workers (HCWs). Although PEP is the standard of care for occupational exposure to HIV in the United States, in third-world countries such medications are often unavailable and risks to the HCW may be higher. The aims of this study were to assess the incidence and types of blood and body fluid exposure and subsequent use of PEP in traveling HCWs seen at a large travel clinic prior to travel. METHODS: To determine the utility of PEP, we retrospectively evaluated all HCWs presenting for counseling prior to travel for health care delivery. All employees who were seen at the Mayo Travel and Tropical Medicine Clinic from 1999 until July 2002 were included. Analysis was conducted via a chart review as well as an approved questionnaire mailed to all employees still at the Mayo Clinic. RESULTS: Eighty-six HCWs were included in the analysis, and 58 responded to the questionnaire. Of the 86 HCWs reviewed, 55 (64%) were determined to be at high risk for occupational exposure to HIV. Seventy-eight percent of the high-risk HCWs were documented to have been counseled about needlestick avoidance, and 55% brought PEP with them. In the 58 HCWs who returned the questionnaire, there were no reported deep needlesticks. One of the 39 high-risk HCWs who returned the questionnaire (2.6%) had a superficial needle exposure, but the source patient had pretested negative for HIV and therefore the HCW did not use PEP. Nine of the 39 (23%) had a blood splash onto intact skin, and one of these involved a large volume. This source patient also had pretested negative for HIV. None of the HCWs exposed to blood splash took PEP. Two HCWs (5.1%) at high risk had an exposure that would have required PEP if the source patient had not been pretested. CONCLUSIONS: Needlestick exposure and HIV PEP counseling is important for HCWs traveling for health care delivery. Exposure risks appear low but high enough to warrant supplying high-risk HCWs with PEP. HCWs are able to use the recommendations appropriately. Pretesting of surgical patients decreases the likelihood of starting PEP. Carrying a common supply of PEP for a larger group can decrease the cost of PEP.

Adult↗
PubMed1989

Relationship of DUI recidivism to moral reasoning, sensation seeking, and MacAndrew alcoholism scores.

115 convicted male DUI offenders were treated with Moral Reconation Therapy during their incarceration. Postrelease recidivism status (arrests) was correlated with the pretest, posttest, and change scores on the MacAndrew Alcoholism Scale, Sensation Seeking Scale, Life-purpose scores, and Moral Reasoning scores. Analysis showed that recidivism correlated positively and significantly with the pretest scores on the MacAndrew scale and approached significance with both pre- and posttest scores on the Sensation Seeking Scale. Recidivism status correlated negatively and significantly with scores on the highest levels of moral reasoning (Scale 6 pretest and posttest and Principled Reasoning pretest).

Adult↗
PubMed2004

Effect of heat modalities on hamstring length: a comparison of pneumatherm, moist heat pack, and a control.

STUDY DESIGN: Prospective, researcher-blinded, repeated-measures, randomized complete block design. OBJECTIVES: To compare the effects of a single treatment of Pneumatherm, moist heat pack, and a control treatment on hamstring muscle length. BACKGROUND: Traditionally, heating modalities have been used to facilitate increases in tissue length. The Pneumatherm has been developed over the past 20 years for use in the clinical treatment of a variety of musculoskeletal pathologies. However, there is no published evidence supporting the use of Pneumatherm for improving muscle length. SUBJECTS: Participants consisted of 30 healthy, college-age males taken from a convenience sampling from the University of Indianapolis student population. METHODS AND MEASURES: Participants received a 3-treatment sequence on consecutive days. Treatments involved applying the determined modality to the posterior thigh using standard treatment protocols. A hand-held dynamometer was used to establish a consistent passive measurement force to measure hamstring muscle length. RESULTS: A mixed-model analysis of variance with pretest-posttest (3 pretest and 3 posttest measures) and treatment sequence of the modalities (6 sequences of Pneumatherm, moist heat, and control) was completed. The only significant effect was for pretest-posttest measures. Post hoc comparisons revealed that the Pneumatherm posttest value was significantly different from all other measures. There were no differences found between pretest scores and the moist heat and control posttest scores. CONCLUSIONS: Our results demonstrate that the Pneumatherm modality is an effective agent for increasing hamstring muscle length following a single 20-minute treatment. In this study, a significant gain in hamstring muscle length was not found following a 1-time treatment with moist heat. The Pneumatherm may be a good option when heat is used to assist in gaining flexibility of the hamstring musculature.

Adult↗
PubMedDate not supplied

Immunization update: a community-based nursing education program.

BACKGROUND: Nurses play key roles as advocates, educators, and researchers to eliminate barriers to access as well as educate the public on the importance of vaccines for children in the United States. METHOD: Fifty-four nurses attending a community-based immunization program completed a pretest questionnaire which included identification of related practice behaviors and general knowledge questions. Twenty-four responded to a similar posttest survey 6 months later. The investigators compared knowledge pretest and posttest scores with a t test. Behavioral changes were compared between the pretest and posttest group by analyzing the percentage of change between the time period. RESULTS: The mean score in the knowledge section increased significantly from a pretest mean of 52% to 75% during the posttest period (p < 005). Behavior change was not statistically significant because of the low number of posttest responses indicating actual immunization practices in the clinical setting. The investigators analyzed trends in practice by comparing percentages of responses. CONCLUSION: These findings suggest that a multifaceted, community-based nursing continuing education program including both local, ethnic community perspectives and information related to the latest standards of practice can impact knowledge levels and some practice behaviors.

Child↗
PubMedDate not supplied

Effects of an educational bereavement program on health care professionals' perceptions of perinatal loss.

BACKGROUND: The purpose of this study was to examine the differences in health care professionals' perceptions of perinatal loss situations before and after an educational program on perinatal bereavement. METHOD: A quasi-experimental design was used in a pretest and posttest format. RESULTS: Scores were significantly higher (p = .000) on each of the posttest vignettes. Overall scores were lowest for the miscarriage pretest, whereas scores for the pretest vignettes for the stillbirth and neonatal loss were similar. A similar pattern occurred in the posttest vignette scores. CONCLUSION: Health care professionals' perceptions of the emotional care needs of families experiencing perinatal loss were significantly increased after an educational program. The miscarriage vignette had the largest change score and the lowest mean scores on the pretest and posttest, which indicates professionals do not view miscarriage as significant a loss as stillbirth and neonatal loss.

Abortion, Induced↗
PubMed2006

Tracking the development of professional values in undergraduate nursing students.

In the current nursing shortage, nurses are frequently making significant patient care decisions concerning value-laden clinical issues. A program evaluation study was conducted to track professional values over time from entry into a baccalaureate program to graduation. Nursing students completed a survey measuring professional values upon entry into and exit from the program. Comparative analysis of pretest and posttest group means demonstrated statistically significant increases in total scores. The highest pretest value items were also the highest on the posttest, with the addition of patient advocacy. Patient advocacy jumped 16 places from pretest to posttest to become the highest-ranked statement upon exit from the program. All of the values rated as least valued at pretest remained least valued at posttest; however, the means of all but two (participating in nursing research and providing consumer education about products/services) increased significantly. The value statements with mean scores that increased significantly centered on aspects of nursing practice less visible to the lay public and involving interaction with other health care providers.

Codes of Ethics↗
PubMed1997

Laboratory evaluation in the diagnosis of Lyme disease.

PURPOSE: To provide a qualitative evaluation of the predictive value of the laboratory diagnosis of Lyme disease and to use the resultant data to formulate guidelines for clinical diagnosis. DATA SOURCES: A MEDLINE search of English-language articles or articles with English-language abstracts published from 1982 to 1996. DATA EXTRACTION: Sensitivity, specificity, and likelihood ratios were calculated, and a random-effects model was used to combine the proportions from the eligible studies. Prespecified criteria were used to determine which studies were eligible for analysis. DATA SYNTHESIS: Laboratory testing in general is not clinically useful if the pretest probability of Lyme disease is less than 0.20 or greater than 0.80. When the pretest probability is 0.20 to 0.80, sequential testing with enzyme-linked immunosorbent assay and Western blot is the most accurate method for ruling in or ruling out the possibility of Lyme disease. CONCLUSIONS: Laboratory testing is recommended only in patients whose pretest probability of Lyme disease is 0.20 to 0.80. If the pretest probability is less than 0.20, testing will result in more false-positive results than true-positive results; a negative test result in this situation effectively rules out the disease.

Bacteriological Techniques↗
PubMed1998

Sensitivity and specificity of a rapid whole-blood assay for D-dimer in the diagnosis of pulmonary embolism.

BACKGROUND: Patients with suspected pulmonary embolism often have nondiagnostic lung scans and may present in circumstances where lung scanning is unavailable. Levels of D-dimer, a fibrin-specific product, are increased in patients with acute thrombosis; this may simplify the diagnosis of pulmonary embolism. OBJECTIVE: To determine the sensitivity and specificity of a whole-blood D-dimer assay in patients with suspected pulmonary embolism and in subgroups of patients with low pretest probability of pulmonary embolism or nondiagnostic lung scans. DESIGN: Prospective cohort. SETTING: Four tertiary care hospitals. PATIENTS: 1177 consecutive patients with suspected pulmonary embolism. MEASUREMENTS: All patients underwent an assessment of pretest probability by use of a standardized clinical model, a D-dimer assay, ventilation-perfusion lung scanning, and bilateral compression ultrasonography. Patients in whom pulmonary embolism was not initially diagnosed were followed for 3 months. Accordingly, patients were categorized as positive or negative for pulmonary embolism. RESULTS: Of the 1177 patients, 197 (17%) were classified as positive for pulmonary embolism. Overall, the D-dimer assay showed a sensitivity of 84.8% and a specificity of 68.4%. In 703 patients (3.4%) with a low pretest probability of pulmonary embolism, the likelihood ratio associated with a negative D-dimer test result was 0.27, resulting in a posterior probability of 1.0% (95% CI, 0.3% to 2.2%). In 698 patients with nondiagnostic lung scans (previous probability, 7.4%), the likelihood ratio associated with a negative D-dimer test result was 0.36, resulting in a posterior probability of 2.8% (CI, 1.4% to 4.8%). CONCLUSIONS: A normal D-dimer test result is useful in excluding pulmonary embolism in patients with a low pretest probability of pulmonary embolism or a nondiagnostic lung scan.

Algorithms↗
PubMed2001

Management of suspected deep venous thrombosis in outpatients by using clinical assessment and D-dimer testing.

BACKGROUND: When deep venous thrombosis is suspected, objective testing is required to confirm or refute the diagnosis. OBJECTIVE: To determine whether the combination of a low clinical suspicion and a normal D -dimer result rules out deep venous thrombosis. DESIGN: Prospective cohort study. SETTING: Three tertiary care hospitals in Canada. PATIENTS: 445 outpatients with a suspected first episode of deep venous thrombosis. INTERVENTIONS: Patients were categorized as having low, moderate, or high pretest probability of thrombosis and underwent whole-blood D -dimer testing. Patients with a low pretest probability and a negative result on the D -dimer test had no further diagnostic testing and received no anticoagulant therapy. Additional diagnostic testing was done in all other patients. MEASUREMENTS: Venous thromboembolic events during 3-month follow-up. RESULTS: 177 (40%) patients had both a low pretest probability and a negative D -dimer result. One of these patients had deep venous thrombosis during follow-up (negative predictive value, 99.4% [95% CI, 96.9% to 100%]). CONCLUSION: The combination of a low pretest probability of deep venous thrombosis and a negative result on a whole-blood D -dimer test rules out deep venous thrombosis in a large proportion of symptomatic outpatients.

Ambulatory Care↗
PubMed1999

Use of ELISA to measure antinuclear antibodies in children with juvenile rheumatoid arthritis.

OBJECTIVE: To compare a series of commercial ELISA tests with an indirect immunofluorescent antibody (IFA) test for the detection of antinuclear antibodies (ANA) in children with juvenile rheumatoid arthritis (JRA). METHODS: Sera from 178 patients with JRA (88 pauciarticular, 68 polyarticular, 22 systemic) were compared with 26 healthy pediatric subjects. Twenty-one samples from patients with systemic lupus erythematosus (SLE) were also tested. All samples were analyzed by IFA and by 3 commercial ELISA methods. Concordance of ELISA results with IFA results (selected standard) were used as a measure of performance. Sensitivity and specificity were calculated for each test and likelihood ratios (LR) were established for IFA and ELISA in pauciarticular and polyarticular JRA sera. The increment in pretest probability was then obtained for each test as an additional measure of test performance. RESULTS: IFA rendered positive results on 18-77% of the JRA sera depending upon the subset, 100% of SLE sera, and 15% of normal patient sera. Using IFA as the standard, correspondence with positive results among patients with JRA ranged from 0 to 74% for the 3 ELISA tests, while it ranged from 5 to 73% in IFA negative sera. IFA tests showed intermediate range likelihood ratios (0.3, 0.5, 3.5, and 5) and increments in pretest probability ranging from 25 to 45%. While one of the ELISA tests attained 50% of increment in pretest probability for the positive test, it showed 0% increment as a negative test. The other 2 ELISA tests incremented the pretest probability from 0 to 25%. CONCLUSION: Our findings indicate that in JRA, the lack of correspondence with the historic standard IFA precludes the use of ELISA tests for detection of ANA. In addition, IFA out-performs ELISA by a substantial degree when "clinical utility" analysis of test performance is utilized. Detection of ANA in children with JRA should either continue to rely on IFA or be based on a different set of antigens if an ELISA format is chosen.

Antibodies, Antinuclear↗
PubMed1999

Medical ethics curriculum for surgical residents: results of a pilot project.

INTRODUCTION: This study sought to develop and evaluate a medical ethics curriculum designed specifically for surgical residents. METHODS: The learning needs of surgical residents relevant to ethics were determined by using a structured literature review and synthesis strategy. We identified 5 primary areas of importance for ethics education for surgical residents: withdrawing and withholding treatment, advance directives, do-not-resuscitate orders, informed consent, and communicating bad news. Learning objectives were developed, and teaching plans were designed for four 90-minute interactive teaching episodes on the basis of adult learning principles. We surveyed residents using a published survey instrument modified for surgery to identify residents' beliefs about the usefulness of ethics training, confidence in addressing ethical issues, and factual knowledge of ethics questions. RESULTS: Twenty surgical residents at a single institution completed the pretest and posttest close-ended surveys. Results showed that although 88% had formal ethics exposure in medical school, 93% considered ethics education at the resident level to be a "very important" or "important" topic. Residents' confidence in addressing ethical issues showed statistically significant improvement between pretest and posttest surveys for 13 of 23 items. There were no statistically significant linear relationships between postgraduate year of residency and the pretest confidence items or the number of correct responses on the pretest multiple-choice items. CONCLUSIONS: Despite the prevalence of ethics education during medical school, surgical residents welcome formal instruction on numerous ethical issues pertinent to surgical practice. A focused curriculum can be developed that has a measurable impact on residents' confidence in addressing ethical issues.

Adult↗
PubMed1999

Efficacy of a modified politzer apparatus in management of eustachian tube dysfunction in adults.

This study evaluates the efficacy of politzeration on eustachian tube dysfunction following airplane travel using an automated, hand-held device that controls the volume velocity of air flow. Fourteen adults with eustachian tube dysfunction following airplane travel comprised the experimental group. They received politzeration over a period of 6 weeks on a twice-a-week basis. Fourteen adults with eustachian tube dysfunction following airplane travel comprised the control group. They were untreated. Complete audiologic and otolaryngologic evaluations were performed at the pretest and after politzeration treatment was completed. The results revealed a substantial, significant improvement in the mean tympanometric peak pressure from pretest to final post-treatment retest in the experimental, but not the control, subjects. The mean air-bone gap increased significantly from pretest to final post-treatment retest in the control, but not the experimental, subjects. Of the experimental subjects with abnormal tympanometric peak pressures at the pretest, resolution to within normal limits occurred in 71 percent of the experimental subjects versus 21 percent of the control subjects. These results suggest the potential feasibility of treatment of aerotitis media in adults with this modified Politzer method using the automated apparatus.

Acoustic Impedance Tests↗