Did death certificates and a death review process agree on lung cancer cause of death in the National Lung Screening Trial?

BACKGROUND/AIMS: Randomized controlled trials frequently use death review committees to assign a cause of death rather than relying on cause of death information from death certificates. The National Lung Screening Trial, a randomized controlled trial of lung cancer screening with low-dose computed tomography versus chest X-ray for heavy and/or long-term smokers ages 55-74 years at enrollment, used a committee blinded to arm assignment for a subset of deaths to determine whether cause of death was due to lung cancer. METHODS: Deaths were selected for review using a pre-determined computerized algorithm. The algorithm, which considered cancers diagnosed during the trial, causes and significant conditions listed on the death certificate, and the underlying cause of death derived from death certificate information by trained nosologists, selected deaths that were most likely to represent a death due to lung cancer (either directly or indirectly) and deaths that might have been erroneously assigned lung cancer as the cause of death. The algorithm also selected deaths that might be due to adverse events of diagnostic evaluation for lung cancer. Using the review cause of death as the gold standard and lung cancer cause of death as the outcome of interest (dichotomized as lung cancer versus not lung cancer), we calculated performance measures of the death certificate cause of death. We also recalculated the trial primary endpoint using the death certificate cause of death. RESULTS: In all, 1642 deaths were reviewed and assigned a cause of death (42% of the 3877 National Lung Screening Trial deaths). Sensitivity of death certificate cause of death was 91%; specificity, 97%; positive predictive value, 98%; and negative predictive value, 89%. About 40% of the deaths reclassified to lung cancer cause of death had a death certificate cause of death of a neoplasm other than lung. Using the death certificate cause of death, the lung cancer mortality reduction was 18% (95% confidence interval: 4.2-25.0), as compared with the published finding of 20% (95% confidence interval: 6.7-26.7). CONCLUSION: Death review may not be necessary for primary-outcome analyses in lung cancer screening trials. If deemed necessary, researchers should strive to streamline the death review process as much as possible.

Parent/Child training to increase preteens' calcium, physical activity, and bone density: a controlled trial.

PURPOSE: To test effects of parent/child training designed to increase calcium intake, bone-loading physical activity (PA), and bone density. DESIGN: Two-group randomized controlled trial. SETTING: Family-based intervention delivered at research center. SUBJECTS: 117 healthy children aged 10-13 years (58.1% female, 42.7% Hispanic, 40.2% White). Ninety-seven percent of participants had at least one parent graduate from high school and 37.2 % had at least one parent graduate from a 4-year university. INTERVENTION: Children and parents were randomly assigned to diet and exercise (experimental) or injury prevention (control) interventions. Children were taught in eight weekly classes how to engage in bone-loading PA and eat calcium-rich foods or avoid injuries. Parents were taught behavior management techniques to modify children's behaviors. MEASURES: Measures at baseline and at 3, 9, and 12 months included 24-hour diet and PA recalls, and bone mineral density (BMD) by dual-energy x-ray absorptiometry. ANALYSIS: Analysis of variance and generalized estimating equations (GEE) assessed group by time differences. Comparisons were conducted separately for boys and girls. RESULTS: For boys, cross-sectional differences between experimental and control groups were achieved for 3- and 9-month calcium intake (1352 vs. 1052 mg/day, 1298 vs. 970 mg/day, p < .05). For girls, marginal cross-sectional differences were achieved for high-impact PA at 12 months (p < .10). For calcium intake, a significant group by time interaction was observed from pretest to posttest for the full sample (p = .008) and for girls (p = .006) but not for boys. No significant group by time differences in calcium were observed across the follow-up period. No group by time differences were observed for high-impact PA. Among boys, longitudinal group by time differences reached significance for total hip BMD (p = .045) and femoral neck BMD (p = .033), even after adjusting for skeletal growth. Similar differential increases were observed among boys for bone mineral content (BMC) at the hip (p = .068) and total body (p = .054) regions. No significant group by time interaction effects were observed for girls at any bone site for BMD. For BMC, control girls showed a significant increase (p = .03) in spine BMC compared to intervention girls. CONCLUSION: This study demonstrated that parent/preteen training can increase calcium intake and attenuate the decline in high-impact PA. Results suggest that more powerful interventions are needed to increase activity levels and maximize bone mineral accrual during preadolescent years.

Strength vs aerobic training in children with cystic fibrosis: a randomized controlled trial.

STUDY OBJECTIVE: Exercise has the potential to improve the ability of a patient with cystic fibrosis (CF) to cope with the physical demands of everyday life, and may improve prognosis. The purpose of this study was to compare the effects of a home-based, semi-supervised, upper-body strength-training regimen with a similarly structured aerobic training regimen. DESIGN: Data were collected during a 1-year randomized clinical trial. SETTING: Counselors conducted in-home visits with the participants once per week for the first 8 weeks followed by monthly visits for the remainder of the study. PATIENTS: Sixty-seven patients with CF, aged 8 to 18 years, participated in the trial. INTERVENTION: Participants in both exercise conditions were encouraged to exercise at least three times per week for 1 year. Each child in the aerobic group was given a stair-stepping machine, and each child in the upper-body strength training group was given an upper-body-only weight-resistance machine. MEASURES AND RESULTS: Aerobic fitness, pulmonary function, quality of life, and strength were measured at baseline, at 6 months, and at 12 months. Strength training increased the maximum weight lifted for biceps curls significantly more than aerobic training (p < 0.02). However, this differential did not remain significant after control for increase in height. Both training procedures were associated with increased strength (p < 0.002) and physical work capacity (PWC) [p < 0.033]. CONCLUSIONS: We concluded that strength and aerobic training may increase upper-body strength, and that both types of training may increase PWC for children with CF. Future trials should be conducted with no-training control subjects and larger samples to increase statistical power.

The National Lung Screening Trial's Endpoint Verification Process: determining the cause of death.

BACKGROUND: Randomized controlled trials (RCTs) evaluating cancer screening modalities usually employ cause-specific mortality as their primary endpoint. Because death certificate cause of death can be inaccurate, RCTs frequently use review committees to assign an underlying cause of death. We describe the National Lung Screening Trial's (NLST's) death review approach, the Endpoint Verification Process (EVP), which strives to minimize errors in assignment of cause of death due to lung cancer. METHODS: Deaths selected for review include those with a notation of lung cancer on the death certificate and those occurring among participants ever diagnosed with lung cancer. Other criteria that trigger death review include, but are not limited to, death within 6 months of a screen suspicious for lung cancer and death within 60 days of certain diagnostic evaluation procedures associated with a screen suspicious for lung cancer or a lung cancer diagnosis. EVP requires concordance on whether death was due to lung cancer. Deaths are first reviewed by the EVP chair. If concordance is not achieved, the death is next reviewed by an Endpoint Verification Team (EVT) member. If concordance between the chair- and member-assigned cause of death is not achieved, the death is next reviewed by a group of at least three EVT members. Cause of death is assigned at the step in which concordance was achieved, or if necessary, at the team review. CONCLUSIONS: NLST's EVP is designed to produce a highly accurate count of lung cancer deaths.

The effects of a physical activity and nutrition intervention on body dissatisfaction, drive for thinness, and weight concerns in pre-adolescents.

The primary aim was to examine the effects of a physical activity and nutrition intervention on Body Dissatisfaction, Drive for Thinness, and Weight Concerns in pre-adolescents. Eighty-four 10-12 years old were studied as part of a larger trial of a family-based physical activity and nutrition intervention. Forty-nine children participated in the 8-week intervention (35 in control group) and completed Body Dissatisfaction, Drive for Thinness, and Weight Concerns measures at baseline and post-test. Participants in both groups showed positive but non-significant changes in body image and Drive for Thinness following the trial, but there were no significant between group differences. This was the first study to examine the effects of a physical activity and nutrition intervention on body image and related variables in pre-adolescents. Body Dissatisfaction, Drive for Thinness, and Weight Concerns were not positively or negatively influenced by the intervention.

Characteristics that predict locating and interviewing mothers identified by a state birth defects registry and vital records.

BACKGROUND: State vital records are often used to select population-based controls in record-linkage studies of birth defects. However, locating and contacting individuals based on these data sources to collect additional data can be a challenge. METHODS: A large case-control study of air quality and birth defects was conducted in 7 Texas counties in which cases were selected from the Texas Birth Defects Registry and controls from state vital records. In 2004, data from these sources were used to trace mothers of cases and controls who delivered babies in the year 2000 (n=2477) for participation in a computer-assisted telephone interview. A number of factors that predicted whether an individual would be located and interviewed were identified. RESULTS: Between March and August 2004, 38% of the mothers were located, and 38% of the located mothers were interviewed. Case mothers were more likely than control mothers to be located (44 vs. 30%) and, if located, to be interviewed (43 vs. 31%). We compared the characteristics of mothers who were not located (case n=760; control n=777), mothers who were located but not interviewed (case n=344; control n=236), and mothers who were interviewed (case n=256; control n=104). Among both cases and controls, older mothers (>or=30 years) were more likely than younger mothers to be located, and non-Hispanic black mothers were least likely to be located and interviewed. CONCLUSIONS: Despite the utility of vital records as a source of population-based controls in record-linkage analyses, the poor response rate discourages the use of these data sources to contact individuals for a follow-up study 4 years after delivery.

Selected Risk Factors for Cancer among Koreans Residing in California.

Preliminary analysis of data (N=2,441) drawn from an ongoing population-based study of people of Korean descent who reside in California revealed the presence of selected cancer risk factors, especially tobacco use and lack of vigorous exercise. Men and women differed in cancer risks, with men being more likely than women to be smokers, less likely to exercise, more likely to be obese, and more likely to consume alcohol. Although relationships between demographic characteristics and cancer risks differed in strength by gender, patterns of correlation were similar among men and women. Future studies should explore the relationship between lifestyle and health risk interactions by gender in greater detail.