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Assessment of health knowledge after "a healthy adventure".

This study evaluated the general health education program for third graders at Hult Health Education Center (Hult HEC). A quasi-experimental, nonequivalent pretest-posttest control group design with four groups was employed to collect pretest and posttest data from 168 third graders. The four groups included a control group, a traditional classroom health education group, a group that visited Hult HEC, and a group that visited Hult HEC and incorporated center curricular materials in the classroom. Analysis of covariance (ANCOVA) was calculated to test for posttest differences among the four groups, while reducing the effects of initial group pretest score differences. A statistically significant difference occurred in posttest scores among the four groups (F = 120.62, df = 4, 163, p = .0001). Post hoc testing revealed the best results were obtained when combining curricular materials with a visit to the Hult HEC.

Analysis of Variance↗

Evaluation of a theater production about eating behavior of children.

This study evaluated "All's Well That Eats Well," a theater production performed in 20 schools in the Twin Cities, Minn., metropolitan area in winter 2000. The production sought to change food-related knowledge and food choices concerning fruits and vegetables among children in grades 1-6. The study used a pretest-posttest design with two randomly-assigned, sequential intervention-control groups (N = 4,093). All students completed surveys prior to and then following the theater production and the classroom and home activities. No differences existed between the groups at pretest. Significant differences occurred in food-related knowledge, food choices, and food recall from pretest to posttest for all students. Significant differences also occurred between intervention groups in food-related knowledge and food choices. The study indicates that professional theater productions in schools can create at least a short-term effect on children's nutrition knowledge and behavior.

Child↗

Evaluation of a child abuse prevention curriculum for third-grade students: assessment of knowledge and efficacy expectations.

Researchers investigated the effects of a child abuse prevention program on third-grade students' knowledge of child abuse and efficacy expectations regarding abusive situations. Three hundred forty-one students completed the 26-item pretest and posttest questionnaires (n = 166 for the intervention group, n = 175 for the control group). Results indicated a statistically significant increase in child abuse knowledge from pretest to posttest with the intervention group, with no change in knowledge for the control group. However, no significant increases occurred in efficacy expectations regarding abusive situations from pretest to posttest for either the intervention or control groups. Results from this study can be used to improve child abuse prevention programs through addressing program components that may affect factors other than student knowledge of abuse.

Child↗

Mixed carbohydrate supplementation increases carbohydrate oxidation and endurance exercise performance and attenuates potassium accumulation.

We studied the effects of different CHO supplements on exercise metabolism (1 hr at 75% VO2max) and performance (fatigue time at 85% VO2max) in 8 male endurance athletes (VO2max = 68.8 +/- 3.8 ml.kg-1.min-1. Four treatments were administered in a randomized, double-blind fashion: Trial A = 3-day pretest, postexercise supplementation (177 kcal [81% carbohydrate, 19% protein] consumed < 10 min after exercise) + 600 ml 8% glucose polymers/ fructose 1 hr pretesting + 600 ml 8% glucose polymers/glucose during testing; Trial B = placebo during 3-day pretest + remainder same as Trial A; Trial C = placebo at all time points; and Trial D = same as Trial B with 8% glucose 1 hr before the test as well as during the test. Time to fatigue at 85% VO2max (increases 24%) and total CHO oxidation were greater for A versus C (p < .05). Plasma glucose concentration was higher for A and B versus C, while increases in plasma potassium concentration were attenuated for A versus C (both p < .05). None of the supplements had differential effects upon hematocrit, plasma sodium [Na+] and lactate, VO2, or rating of perceived exertion during exercise. Three-day preexercise protein + carbohydrate supplements followed by 1-hr pre- and during-exercise mixed carbohydrate supplements increased time to fatigue and carbohydrate oxidation and attenuated rises in plasma [K+] compared to placebo.

Adult↗

Teaching safety: evaluation of a children's village in Maryland.

OBJECTIVES: The purpose of this study was to evaluate Children's Village, a life safety education facility for children. SETTING: The study took place in Washington County, Maryland, a rural county. METHODS: Eight elementary schools with 20 second grade classrooms (410 students aged 7 and 8) were selected to participate. Using a quasiexperimental design, tests were administered to two cohorts of children before (pretest) and after (post-test) they attended the Children's Village during 1993-4. Parent and teacher surveys were also completed after the program. RESULTS: Among children who attended in December 1993-January 1994, there was a significant improvement in average test scores between the pretest (58% correct) and post-test (78%). Among children who attended in April 1994, there also was a significant improvement in test scores between pretest (74%) and post-test (85%). Among parents, 70% reported that their child learned a great deal at Children's Village and 33% reported having made changes in their home as a result. The parent survey also revealed that 25% of children and 35% of adults did not always wear their seat belts, and 74% of children did not always wear bicycle helmets. Teachers' responses to the program were generally positive. CONCLUSIONS: Children's Village brought together an extensive network of community leaders, parents, and teachers dedicated to safety education of children. The curriculum had a positive impact on children's knowledge and, to a lesser extent, on parents' safety practices. Program impact could be enhanced by more emphasis on automobile restraints and helmets (behaviors that parents reported were not consistently practiced) and by expanding the village services to parents as well as children. Others considering creating similar programs need to identify community leaders willing to commit the time, effort, and resources required to develop and sustain such programs.

Accident Prevention↗

Post-test probability that men in the community with raised plasma ferritin concentrations are hazardous drinkers.

BACKGROUND: Raised plasma ferritin concentrations occur unexpectedly during iron studies done by primary care physicians. Plasma ferritin concentration has been positively associated with alcohol use among men. AIM: To determine the post-test probability that men in the community with raised plasma ferritin concentrations are hazardous drinkers. METHODS: The subjects were 152 men, randomly selected from a city's electoral roll. Nineteen (12.5 (2.7)%, mean (SEM)) admitted to drinking hazardously. The pretest probability of a man being a hazardous drinker was 0.125. This was converted to pretest odds of 0.14. The likelihood ratio (the ratio of the probability of obtaining a raised plasma ferritin concentration in a hazardous drinker (sensitivity) to the probability of obtaining a raised plasma ferritin concentration in a non-hazardous drinker (1-specificity)) was calculated for different plasma ferritin cut off points. RESULTS: A plasma ferritin level of > 652 micrograms/l gave the largest likelihood ratio, 4.16. Post-test odds were obtained by multiplying the pretest odds (0.14) by the likelihood ratio (4.16). A plasma ferritin level of > 652 micrograms/l had a post-test odds for a man being a hazardous drinker of 0.58. This was converted to a post-test probability of 0.37. CONCLUSIONS: Inquiries could usefully be made into the alcohol consumption of men with a plasma ferritin concentration > 652 micrograms/l, as approximately one in three would admit to drinking hazardously.

Adult↗

Prediction of deep myometrial invasion in patients with endometrial cancer: clinical utility of contrast-enhanced MR imaging-a meta-analysis and Bayesian analysis.

PURPOSE: To determine if, in a patient with an endometrial cancer, in addition to the knowledge of tumor grade, preoperative magnetic resonance (MR) imaging findings contribute to treatment stratification and specialist referral. MATERIALS AND METHODS: By using a MEDLINE literature search and institutional pathology reports, pretest probabilities for myometrial invasion were correlated with tumor grade. Likelihood ratios (LRs) were obtained through summary receiver operating characteristics. RESULTS: The mean pretest probabilities of deep myometrial invasion were derived from seven articles (1,875 patients) and from 125 institutional pathology reports. LRs for the prediction of myometrial invasion with contrast-enhanced MR imaging were derived from nine studies (742 patients); positive and negative LRs were 10.11 and 0.1, respectively. The mean weighted pretest probabilities of deep myometrial invasion in patients with tumor grades 1, 2, or 3 were 13%, 35%, or 54%, respectively. Posttest probabilities of deep myometrial invasion for grades 1, 2, or 3 increased to 60%, 84%, or 92%, respectively, for positive and decreased to 1%, 5%, or 10%, respectively, for negative MR imaging findings. CONCLUSION: Use of contrast-enhanced MR imaging significantly affects the posttest probability of deep myometrial invasion in patients with all grades of endometrial cancer and could be used to select patients for specialist referral.

Bayes Theorem↗

Shortening of muscle relaxation time after creatine loading.

The effect of creatine (Cr) supplementation on muscle isometric torque generation and relaxation was investigated in healthy male volunteers. Maximal torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of Tmax were measured during 12 maximal isometric 3-s elbow flexions interspersed by 10-s rest intervals. Between the pretest and the posttest, subjects ingested Cr monohydrate (4 x 5 g/day; n = 8) or placebo (n = 8) for 5 days. Pretest Tmax, CT, and RT were similar in Cr and placebo groups. Also in the posttest, Tmax and CT were similar between groups. However, posttest RT was decreased consistently by approximately 20% (P < 0.05) in the Cr group from the first to the last of the 12 contractions. In addition, the mean decrease in RT after Cr loading was positively correlated with pretest RT (r = 0.82). It is concluded that Cr loading facilitates the rate of muscle relaxation during brief isometric muscle contractions without affecting torque production.

Adolescent↗

No effects of oral ribose supplementation on repeated maximal exercise and de novo ATP resynthesis.

A double-blind randomized study was performed to evaluate the effect of oral ribose supplementation on repeated maximal exercise and ATP recovery after intermittent maximal muscle contractions. Muscle power output was measured during dynamic knee extensions with the right leg on an isokinetic dynamometer before (pretest) and after (posttest) a 6-day training period in conjunction with ribose (R, 4 doses/day at 4 g/dose, n = 10) or placebo (P, n = 9) intake. The exercise protocol consisted of two bouts (A and B) of maximal contractions, separated by 15 s of rest. Bouts A and B consisted of 15 series of 12 contractions each, separated by a 60-min rest period. During the training period, the subjects performed the same exercise protocol twice per day, with 3-5 h of rest between exercise sessions. Blood samples were collected before and after bouts A and B and 24 h after bout B. Knee-extension power outputs were approximately 10% higher in the posttest than in the pretest but were similar between P and R for all contraction series. The exercise increased blood lactate and plasma ammonia concentrations (P < 0.05), with no significant differences between P and R at any time. After a 6-wk washout period, in a subgroup of subjects (n = 8), needle-biopsy samples were taken from the vastus lateralis before, immediately after, and 24 h after an exercise bout similar to the pretest. ATP and total adenine nucleotide content were decreased by approximately 25 and 20% immediately after and 24 h after exercise in P and R. Oral ribose supplementation with 4-g doses four times a day does not beneficially impact on postexercise muscle ATP recovery and maximal intermittent exercise performance.

Adenine Nucleotides↗

Effect of age on the performance of a diagnostic strategy based on clinical probability, spiral computed tomography and venous compression ultrasonography: the ESSEP study.

As the prevalence of PE increases with age, the effect of age on the diagnostic work-up in front of a clinical suspicion of PE deserves exploration. In this retrospective analysis, we used the data from 1041 consecutive suspected PE patients. The patients were divided into three groups according to tertiles of age: under 54 years, 54 to 73 years and above 73 years. The prevalence of PE in patients with respectively low, intermediate and high pretest clinical probability was expressed within each age group. We studied the effect of age on the results observed in three main groups of patients, after performing CT scan and ultrasonography (CUS): (1) patients with inconclusive results; (2) patients with negative findings on both exams and non high pretest clinical probability; (3) patients with positive findings.The prevalence of PE increased significantly with age, in overall, as well as in patients with low or intermediate pretest clinical probability. An analysis according to the three main diagnostic groups showed that: (1) the distribution of inconclusive spiral CT or CUS examinations was not different between age groups; (2) no thromboembolic event occurred in untreated patients with low or intermediate clinical probability aged under 54 years of age, whereas 7 events were diagnosed in patients aged over 73 years (p<0.001); (3) a higher proportion of older patients had a positive result at both spiral CT and CUS examinations. The percentage of positive CT scans in the case of negative or inconclusive CUS results was not different between age groups; conversely, in the case of a negative or inconclusive CT scan, the percentage of positive CUS was higher in older patients. In conclusion, management of elderly suspected PE patients appears to be different from both the work-up and the outcome perspectives.

Age Distribution↗

The use of radionuclide angiography in the diagnosis of coronary artery disease--a logistic regression analysis.

We applied logistic regression analysis to a group of 736 patients with chest pain to determine which radionuclide angiographic (RNA) parameters were most useful in the diagnosis of significant coronary artery disease. The most useful parameters were exercise ejection fraction, exercise heart rate, "ischemia score," and the presence of a regional wall motion abnormality at exercise. Ten clinical variables were used in one logistic regression model to estimate each patient's pretest probability of disease. A second logistic regression model considered these clinical variables and the four important RNA parameters to estimate each patient's posttest probability. These models were applied prospectively to a group of 76 patients with chest pain who did not have a high pretest probability of disease. Twenty-four patients (32%) could be diagnosed with 90% probability; 32 patients (42%) could be diagnosed with 85% probability. RNA testing is therefore helpful in the noninvasive diagnosis of coronary artery disease. However, a majority of patients who do have a low or intermediate pretest probability of disease will require additional testing for a definitive diagnosis.

Cardiac Catheterization↗

Bayesian probability analysis: a prospective demonstration of its clinical utility in diagnosing coronary disease.

One hundred fifty-four patients referred for coronary arteriography were prospectively studied with stress electrocardiography, stress thallium scintigraphy, cine fluoroscopy (for coronary calcifications), and coronary angiography. Pretest probabilities of coronary disease were determined based on age, sex, and type of chest pain. These and pooled literature values for the conditional probabilities of test results based on disease state were used in Bayes' theorem to calculate posttest probabilities of disease. The results of the three noninvasive tests were compared for statistical independence, a necessary condition for their simultaneous use in Bayes' theorem. The test results were found to demonstrate pairwise independence in patients with and those without disease. Some dependencies that were observed between the test results and the clinical variables of age and sex were not sufficient to invalidate application of the theorem. Sixty-eight of the study patients had at least one major coronary artery obstruction of greater than 50%. When these patients were divided into low-, intermediate-, and high-probability subgroups according to their pretest probabilities, noninvasive test results analyzed by Bayesian probability analysis appropriately advanced 17 of them by at least one probability subgroup while only seven were moved backward. Of the 76 patients without disease, 34 were appropriately moved into a lower probability subgroup while 10 were incorrectly moved up. We conclude that posttest probabilities calculated from Bayes' theorem more accurately classified patients with and without disease than did pretest probabilities, thus demonstrating the utility of the theorem in this application.

Angiography↗

Bayesian analysis versus discriminant function analysis: their relative utility in the diagnosis of coronary disease.

Both Bayesian analysis assuming independence and discriminant function analysis have been used to estimate probabilities of coronary disease. To compare their relative accuracy, we submitted 303 subjects referred for coronary angiography to stress electrocardiography, thallium scintigraphy, and cine fluoroscopy. Severe angiographic disease was defined as at least one greater than 50% occlusion of a major vessel. Four calculations were done: (1) Bayesian analysis using literature estimates of pretest probabilities, sensitivities, and specificities was applied to the clinical and test data of a randomly selected subgroup (group I, 151 patients) to calculate posttest probabilities. (2) Bayesian analysis using literature estimates of pretest probabilities (but with sensitivities and specificities derived from the remaining 152 subjects [group II]) was applied to group I data to estimate posttest probabilities. (3) A discriminant function with logistic regression coefficients derived from the clinical and test variables of group II was used to calculate posttest probabilities of group I. (4) A discriminant function derived with the use of test results from group II and pretest probabilities from the literature was used to calculate posttest probabilities of group I. Receiver operating characteristic curve analysis showed that all four calculations could equivalently rank the disease probabilities for our patients. A goodness-of-fit analysis suggested the following relationship between the accuracies of the four calculations: (1) less than (2) approximately equal to (4) less than (3). Our results suggest that data-based discriminant functions are more accurate than literature-based Bayesian analysis assuming independence in predicting severe coronary disease based on clinical and noninvasive test results.

Bayes Theorem↗

Effects of stress reduction on carotid atherosclerosis in hypertensive African Americans.

BACKGROUND AND PURPOSE: African Americans suffer disproportionately higher cardiovascular disease mortality rates than do whites. Psychosocial stress influences the development and progression of atherosclerosis. Carotid intima-media thickness (IMT) is a valid surrogate measure for coronary atherosclerosis, is a predictor of coronary outcomes and stroke, and is associated with psychosocial stress factors. Stress reduction with the Transcendental Meditation (TM) program decreases coronary heart disease risk factors and cardiovascular mortality in African Americans. B-mode ultrasound is useful for the noninvasive evaluation of carotid atherosclerosis. METHODS: This randomized controlled clinical trial evaluated the effects of the TM program on carotid IMT in hypertensive African American men and women, aged >20 years, over a 6- to 9-month period. From the initially enrolled 138 volunteers, 60 subjects completed pretest and posttest carotid IMT data. The assigned interventions were either the TM program or a health education group. By use of B-mode ultrasound, mean maximum IMT from 6 carotid segments was used to determine pretest and posttest IMT values. Regression analysis and ANCOVA were performed. RESULTS: Age and pretest IMT were found to be predictors of posttest IMT values and were used as covariates. The TM group showed a significant decrease of -0.098 mm (95% CI -0. 198 to 0.003 mm) compared with an increase of 0.054 mm (95% CI -0.05 to 0.158 mm) in the control group (P=0.038, 2-tailed). CONCLUSIONS: Stress reduction with the TM program is associated with reduced carotid atherosclerosis compared with health education in hypertensive African Americans. Further research with this stress-reduction technique is warranted to confirm these preliminary findings.

Black People↗

Teaching electroconvulsive therapy to medical students: effects of instructional method on knowledge and attitudes.

OBJECTIVE: To compare the effects of learning about electroconvulsive therapy (ECT) via live observation to learning via an instructional videotape. METHOD: During their psychiatry clerkship, 122 medical students were randomized using these two educational methods, and their ECT knowledge and attitudes were assessed during the first and last weeks of the 6-week clerkship. RESULTS: For both the knowledge and attitudes measures, the clerkship (time) effect was statistically significant (i.e., posttest scores were higher than pretest scores). The interaction effect was significant for knowledge only (pretest scores for students in the live group were slightly lower at pretest than those for students in the videotape group and slightly higher at posttest). The effect size was very small, however, suggesting little meaningful educational difference between the two instructional methods. CONCLUSION: Both live demonstration and viewing a videotape appear to be effective methods for teaching medical students about ECT.

Clinical Clerkship↗

Contextual interference effects with skilled baseball players.

The learning benefits of contextual interference have been frequently demonstrated in different settings using novice learners. The purpose of the present study was to test such effects with skilled athletic performers. Scheduling differences for biweekly additional ("extra") batting-practice sessions of a collegiate baseball team were examined. 30 players (ns = 10) were blocked on skill and then randomly assigned to one of three groups. The random and blocked groups received 2 additional batting-practice sessions each week for 6 wk. (12 sessions), while the control group received no additional practice. The extra sessions consisted of 45 pitches, 15 fastballs, 15 curveballs, and 15 change-up pitches. The random group received these pitches in a random order, while the blocked group received all 15 of one type, then 15 of the next type, and finally 15 of the last type of pitch in a blocked fashion. All subjects received a pretest of 45 randomly presented pitches of the three varieties. After 6 wk. of extra batting practice, all subjects received two transfer tests, each of 45 trials; one was presented randomly and one blocked. The transfer tests were counterbalanced across subjects. Pretest analysis showed no significant differences among groups. On both the random and blocked transfer tests, however, the random group performed with reliably higher scores than the blocked group, who performed better than the control group. When comparing the pretest to the random transfer test, the random group improved 56.7%, the blocked group 24.8%, and the control group only 6.2%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Matching anonymous pre-posttests using subject-generated information.

Sensitive research issues call for anonymous questionnaires. This makes accurately matching pretests with posttests difficult or impossible. Various subject-generated coding schemes have been developed, but their accuracy has been unknown. This anonymous study, with 745 students, used subject-generated coding to match pretests with posttests. The matching was verified for accuracy with the use of a collateral, anonymous, sticker identification system. The coding system was able to accurately match 75.2% of all the pretest-posttest pairs. An additional 22.1% of the pairs were left unmatched and only 2.7% were matched incorrectly. Subject-generated coding systems can be very effective where confidentiality is important to protect.

Adolescent↗

A course in clinical decision making adaptable to diverse audiences.

Faculty at the University of Pennsylvania have developed a prototype course in clinical decision making that can be adapted to the diverse backgrounds of a variety of medical audiences. The course was offered in its entirety to third and fourth-year medical students and in abbreviated form to two postgraduate audiences (community and university-based physicians) during 1982. Methods were developed for content, process, and outcome evaluation for the courses; the latter consisted of pretest and posttest comparisons of performance on a written examination. Ninety-four individuals attended one or more sessions of the three courses. All courses were very favorably received, although the postgraduate audiences perceived less clinical relevance than educational relevance in the material (p less than 0.05). The medical students performed better on the pretest than either group of physicians, with the student-university physician difference reaching statistical significance (p less than 0.01). Nevertheless, all groups performed better on the posttest than on the pretest (p less than 0.001) and the degree of improvement was no different among the groups (p greater than 0.29). We conclude that our course's concepts and skills can be effectively adapted to and assimilated by physicians at all levels of training and experience.

Curriculum↗