Biomedical subjects

D M Murray

Publications and source records attributed to D M Murray.

At least 55 records · Page 3Linked to original sources

PubMed1998

A trivariate distribution for the height, weight, and fat of adult men.

Using exploratory data analysis, probability plots, scatterplots, and computer animations to rotate and visualize the data, we fit a trivariate Normal distribution to data for the height, the natural logarithm of body weight, and the body fat for 646 men between the ages of 50 and 80 years as reported by the medical staff of the U.S. Veterans Administration's "Normative Aging Study" in Boston, MA. Although these data do not include any children, women, or young men, the measurements represent the best data that we could find through a 4-year search. We believe that these data are well measured and reliable for men in the specified age range and that these data reveal an interesting statistical pattern for use in probabilistic PBPK models.

Adipose Tissue↗

PubMed1998

Social settings and situations of underage drinking.

OBJECTIVE: Social settings and situations of underage drinking were described for students from 15 communities in Minnesota and Wisconsin. Reports of their last drinking event, including setting, number of persons drinking with them, number of those persons under age 21, and whom they were with, were examined. The role of these variables in the prediction of having five or more drinks on one occasion was assessed. METHOD: Ninth graders (n = 2,269) and 12th graders (n = 2,377) who reported using alcohol in the last 30 days were included in the sample from a nested cross-sectional survey design. Bivariate analyses were performed between the situational variables and gender, number of older siblings and drinking behavior. Chi-square statistics were divided by an estimate of the design effect and multivariate analyses used mixed-model regression to correct for the nesting of individuals within communities. RESULTS: Situations and settings of drinking differed according to age and drinking behavior. Twelfth graders were less likely to drink with parents or other adults than 9th graders and more likely to drink in someone else's home, and in large groups where nearly everyone was underage. Persons reporting having five or more drinks on one occasion in the last 2 weeks were more likely to report drinking with peers, in large groups of underage persons and away from home. CONCLUSIONS: Interventions to reduce use of alcohol by youth must focus on the context in which the drinking is taking place in addition to other factors. Policy or educational interventions that seek to alter the situations and settings of underage drinking may be effective in reducing consumption of alcohol in adolescents.

Adolescent↗

PubMed1998

Changing fruit and vegetable consumption among children: the 5-a-Day Power Plus program in St. Paul, Minnesota.

OBJECTIVES: A randomized school based trial sought to increase fruit and vegetable consumption among children using a multicomponent approach. METHODS: The intervention, conducted in 20 elementary schools in St. Paul, targeted a multiethnic group of children who were in the fourth grade in spring 1995 and the fifth grade in fall 1995. The intervention consisted of behavioral curricula in classrooms, parental involvement, school food service changes, and industry support and involvement. Lunchroom observations and 24-hour food recalls measured food consumption. Parent telephone surveys and a health behavior questionnaire measured psychosocial factors. RESULTS: The intervention increased lunchtime fruit consumption and combined fruit and vegetable consumption, lunchtime vegetable consumption among girls, and daily fruit consumption as well as the proportion of total daily calories attributable to fruits and vegetables. CONCLUSIONS: Multicomponent school-based programs can increase fruit and vegetable consumption among children. Greater involvement of parents and more attention to increasing vegetable consumption, especially among boys, remain challenges in future intervention research.

Child↗

PubMed1998

Adolescents engaging in unhealthy weight control behaviors: are they at risk for other health-compromising behaviors?

OBJECTIVES: This study sought to determine whether adolescents engaging in weight control behaviors are at increased risk for tobacco, alcohol, and marijuana use; suicide ideation and attempts; and unprotected sexual activity. METHODS: Data were collected on a nationally representative sample of 16,296 adolescents taking part in the 1993 Youth Risk Behavior Survey. RESULTS: Adolescents using extreme weight control behaviors were at increased risk for health-compromising behaviors, while associations with other weight control behaviors were weak and inconsistent. CONCLUSIONS: The findings have relevance to clinical work with youth, provide a better understanding of disordered eating, and open up a number of opportunities for future research.

Adolescent↗

PubMed1998

The effects of community policies to reduce youth access to tobacco.

OBJECTIVES: This study tested the hypothesis that adoption and implementation of local policies regarding youth access to tobacco can affect adolescent smoking. METHODS: A randomized community trial was conducted in 14 Minnesota communities. Seven intervention communities participated in a 32-month community-organizing effort to mobilize citizens and activate the community. The goal was to change ordinances, merchant policies and practices, and enforcement practices to reduce youth access to tobacco. Outcome measures were derived from surveys of students before and after the intervention and from tobacco purchase attempts in all retail outlets in the communities. Data analyses used mixed-model regression to account for the clustering within communities and to adjust for covariates. RESULTS: Each intervention community passed a comprehensive youth access ordinance. Intervention communities showed less pronounced increases in adolescent daily smoking relative to control communities. Tobacco purchase success declined somewhat more in intervention than control communities during the study period, but this difference was not statistically significant. CONCLUSIONS: This study provides compelling evidence that policies designed to reduce youth access to tobacco can have a significant effect on adolescent smoking rates.

Adolescent↗

PubMed1997

Improving cancer pain management in communities: main results from a randomized controlled trial.

The purpose of this randomized controlled community trial is to evaluate the effects of a community intervention utilizing opinion leaders and educational strategies on the cancer pain management knowledge, attitudes, and the practices of physicians and nurses, and cancer pain reported by patients. Six Minnesota communities participated in the study. The three communities randomized to the intervention received educational programs over 15 months. The clinical community opinion leaders participated in a minifellowship, developed community task forces, and interacted with their peers. This strategy was reinforced with community outreach programs, clinical practice guidelines, educational materials, and media events. The primary study end point was patients' pain intensity score. Comparing intervention to control communities, pain prevalence declined slightly, pain management index improved slightly, pain intensity scores increased slightly, patient and family attitude scores did not change, and physicians' and nurses' knowledge and attitude scores improved slightly. None of these changes, however, reached statistical significance. Participation in at least one intervention program improved physicians' and nurses' knowledge and attitude scores that approached statistical significance. Our results suggest that community opinion leaders combined with other educational programs may improve cancer pain management, but this strategy requires further study. The results suggest that more intense intervention application may be effective. Effective strategies to improve cancer pain management remain elusive.

Cohort Studies↗

PubMed1997

Joint analysis of three U.S. community intervention trials for reduction of cardiovascular disease risk.

During the 1980s three comprehensive community-based heart disease prevention trials were conducted in the United States. The Stanford Five-City Project, Minnesota Heart Health Program, and Pawtucket Heart Health Program involved 12 cities; six received a 5-8 year multifactorial risk reduction program. This analysis pools data from the three studies to delineate the common intervention effects with greater sample size and power than could be attained by the single studies. Time trends were estimated for cigarette smoking, blood pressure, total cholesterol, body mass index, and coronary heart disease mortality risk in women and men aged 25-64 years. The joint estimates of intervention effect were in the expected direction in nine of 12 gender-specific comparisons; however, these were not statistically significant. The results illustrate the analytic challenges of evaluating community-based prevention trials and point to the smaller than expected net differences, rather than small sample size, as the reason for few statistically significant effects in the three U.S. prevention trials.

Blood Pressure↗

PubMed1997

Acute colonic pseudo-obstruction after total hip replacement.

Acute colonic pseudo-obstruction is a poorly recognised and potentially fatal complication of hip surgery. Between 1991 and 1994 six patients were observed who required laparotomy after failure of medical management. In three the indication was signs of peritonism, while in the other three exploration was required to exclude segmental ischaemia and to decompress the bowel. In all, there was no evidence of mechanical obstruction. Patients having total hip replacement are at risk of developing pseudo-obstruction due to their age, comorbidity, high doses of analgesics and the nature of the operation. If postoperative ileus persists for more than 48 hours acute colonic pseudo-obstruction should be suspected and confirmed by plain radiography. Prompt recognition and treatment with early referral to a colorectal unit are indicated. Laparotomy appears to carry less risk than that for patients with idiopathic pseudo-obstruction, but should be performed only if colonic ischaemia is suspected.

Acute Disease↗

PubMed1997

Lifetime cocaine use and cardiovascular characteristics among young adults: the CARDIA study.

OBJECTIVES: Cocaine is a central nervous system stimulant associated with cardiovascular disease risk factors, morbidity, and mortality. Despite these demonstrated relationships, it has been difficult to assess the long-term cardiovascular consequences of cocaine use. METHODS: The Coronary Artery Risk Development in Young Adults study provides an opportunity to evaluate the association of lifetime cocaine use with cardiovascular disease risk factors in a randomly sampled biethnic cohort of men and women of varied socioeconomic status, aged 20 to 32 in 1987. RESULTS: More extensive cocaine use experience was associated with being White, older, and less educated, regardless of sex. Higher levels of licit and illicit substance use behavior were reported by those reporting more extensive cocaine experience; however, most cardiovascular disease risk factors such as systolic and diastolic blood pressure, heart rate, hypertension, physical activity, and anthropometric measurements were not related to lifetime cocaine experience. CONCLUSIONS: In this age group, the detrimental cardiovascular effects of cocaine may be limited to acute effects. Further studies are needed to determine whether continued exposure is related to cardiovascular disease risk factors later in life.

Adult↗

PubMed1997

Adolescent smokers' provision of tobacco to other adolescents.

OBJECTIVES: This study examined adolescent smokers provision of tobacco to other adolescents. METHODS: Data from a survey of 8th-, 9th-, and 10th-grade students in Minnesota were analyzed by using mixed-model logistic regression. RESULTS: More than two thirds (68.8%) of adolescent smokers had provided tobacco to another adolescent in the previous 30 days. Mother's smoking, number of friends who smoke, owning tobacco merchandise, number of cigarettes smoked in the past week, source of last cigarette (commercial), and recent attempt to buy cigarettes were associated with providing. CONCLUSIONS: The social availability of tobacco to youth needs further examination.

Adolescent↗

PubMed1997

Relationships among alcohol availability, drinking location, alcohol consumption, and drinking problems in adolescents.

We examined relationships among perceived alcohol availability, drinking location, alcohol consumption, and drinking problems. Subjects were 3,372 adolescent drinkers, ages 16-18, who participated in the Communities Mobilizing for Change on Alcohol Project baseline survey. Mixed-model regression was employed to identify predictors of alcohol consumption and drinking consequences. Perceived alcohol availability was significantly associated with higher levels of alcohol consumption for males. Drinking in a public location with higher levels of alcohol consumption for females. Results underscore the importance of youth alcohol assessibility.

Adolescent↗

PubMed1996

Community education for cardiovascular disease prevention. Morbidity and mortality results from the Minnesota Heart Health Program.

The Minnesota Heart Health Program was a community trial of cardiovascular disease prevention methods that was conducted from 1980 to 1990 in three Upper Midwestern communities with three matched comparison communities. A 5- to 6-year intervention program used community-wide and individual health education in an attempt to decrease population risk. A major hypothesis was that the incidence of validated fatal and nonfatal coronary heart disease and stroke in 30- to 74-year-old men and women would decline differentially in the education communities after the health promotion program was introduced. This hypothesis was investigated using mixed-model regression. The intervention effect was modeled as a series of annual departures from a linear secular trend after a 2-year lag from the start of the intervention program. In the education communities, 2,394 cases of coronary heart disease and 818 cases of stroke occurred, with 2,526 and 739 cases, respectively, being seen in the comparison communities. The overall decline in coronary heart disease incidence was 1.8 percent per year in men (p = 0.03) and 3.6 percent per year in women (p = 0.007). For stroke, there were no significant secular trends. The authors recently published findings showing minimal effects of sustained intervention on risk factor levels. In the current report, there was no evidence of a significant intervention effect on morbidity or mortality, either for coronary heart disease or for stroke.

Adult↗

PubMed1996

Patients and family members: the role of knowledge and attitudes in cancer pain.

Cancer pain theoretically comprises sensory, affective, and cognitive dimensions, implying that patients and family members perceive and report cancer pain based on these factors. The study reported here investigated the relationship between specific knowledge and attitudes (cognitive factors), and patients' and family members' reports of pain due to cancer. The relationship between cognitive factors and reports of cancer pain was investigated in interviews with 122 patients and their family members. Pain was measured using the Brief Pain Inventory; knowledge and attitudes were measured using a form previously developed by the authors. Patients' and family members' reports of patient pain and performance status were highly correlated, although family members consistently reported more pain and disability. Using regression analysis, cognitive factors were strongly related to family reports of patients' pain (R2 = 0.27), but contributed little to explaining pain reported by patients themselves (R2 = 0.06). Improved understanding of patients' pain assessments depends on further investigation of other cognitive factors and of sensory and affective factors. Family members' assessments of pain are significantly related to appropriate knowledge and attitudes.

Adult↗

PubMed1996

Alcohol outlet policies and practices concerning sales to underage people.

Little is known about the relationship between alcohol outlet policies and practices in the United States and the likelihood that outlets will sell alcoholic beverages to persons under the legal drinking age. This study assessed the prevalence of such outlet-level policies and practices, and analyzed the relationships between outlet variables and outlets' actual propensity to sell alcoholic beverages to youth. The sample consisted of all outlets licensed for off-premise and a 40% random sample of outlets licensed for on-premise sale of alcoholic beverages in 15 small to medium-sized communities in Minnesota and Wisconsin (USA). Data on outlet characteristics, policies and practices were collected by a telephone survey of the owner or manager of each outlet. In addition, alcohol purchase attempts were conducted at each outlet by youthful-appearing study confederates. Generally, policies and practices that may reduce the likelihood of sales to youth were reported by a minority of outlets. Purchase success was found to be associated with a number of outlet characteristics, policies and practices. The implications of these findings for policy and future research are discussed.

Adolescent↗

PubMed1996

Peer-planned social activities for preventing alcohol use among young adolescents.

The Project Northland peer participation program tested the feasibility of involving students in the planning and promotion of alcohol-free social activities for their peers and to determine whether such participation was associated with reduced alcohol use. The peer program was offered in 20 northeastern Minnesota schools when the study cohort was in seventh grade; students completed a survey in the beginning of sixth grade and at the end of sixth grade and seventh grade. Nearly 50% of the study cohort participated in the program. At the end of seventh grade, after controlling for confounders, an association was observed between student involvement with planning activities and a lower rate of alcohol use. This association was strongest among students who had reported alcohol use at the beginning of sixth grade. This cohort study suggests adolescent involvement in planning their own alcohol-free activities may be an efficacious strategy to prevent or reduce the prevalence of alcohol use among youth. Future studies are warranted to evaluate this association using experimental research designs.

Adolescent↗

PubMed1996

A Monte Carlo study of alternative responses to intraclass correlation in community trials. Is it ever possible to avoid Cornfield's penalties?

Strategies to avoid the penalties of extra variation and reduced degrees of freedom in community trials were compared in Monte Carlo simulations. Three conditions were found necessary to ensure nominal Type I and II error rates: (a) Condition variation must be assessed against assignment unit variation, (b) the critical value for the test statistic must be based on the assignment unit degrees of freedom, and (c) estimation of negative intraclass correlations must be allowed in the analysis. Using other test statistics and other degrees of freedom, and fixing negative intraclass correlations at zero often gave Type I and II error rates far from their nominal levels.

Analysis of Variance↗

PubMed1996

Gauss or Bernoulli? A Monte Carlo comparison of the performance of the linear mixed-model and the logistic mixed-model analyses in simulated community trials with a dichotomous outcome variable at the individual level.

This Monte Carlo study compares performance of the linear and the logistic mixed-model analyses of simulated community trials having event rates of 37%, 13%, or 5%, intraclass correlations between 0.01 and 0.05, and 17 or 5 denominator degrees of freedom. Type I or Type II error rates showed no essential difference between the two analysis methods. They showed depressed error rates when the event rate or the denominator degrees of freedom were small. The authors conclude that in studies with adequate denominator degrees of freedom, the researcher may use either method of analysis but should accept negative estimates of components of variance to avoid depression of error rates.

Analysis of Variance↗

PubMed1996

A meta-analysis of smoking prevention programs after adjustment for errors in the unit of analysis.

This article presents the results of a meta-analysis designed to test the prevailing view that we largely understand why adolescents start to smoke and how to delay it. This view has developed even though none of the major reviews of the last 12 years has adjusted for the important methodological problems that all of those reviews identified as common in the published literature. School-based smoking prevention programs based on peer or social-type programs, published between 1974 and 1991, were included in this meta-analysis. Treatment characteristics were used to predict an effect size after adjustment for study design and population characteristics, and in particular, after a post hoc correction for errors in the original unit of analysis. The results suggest that the average effect for peer or social-type programs is likely to be quite limited in magnitude, and that the reduction in smoking may be only 0.10 standard deviation units, or perhaps 5%. Even under optimal conditions, the reduction in smoking may be only 0.50 to 0.75 standard deviation units, or perhaps 20%-30%.

Adolescent↗