Proper Orthogonal Decomposition Methods for the Analysis of Real-Time Data: Exploring Peak Clustering in a Secondhand Smoke Exposure Intervention.

This work explores a method for classifying peaks appearing within a data-intensive time-series. We summarize a case study from a clinical trial aimed at reducing secondhand smoke exposure via the installation of air particle monitors in households. Proper orthogonal decomposition (POD) in conjunction with a k-means clustering algorithm assigns each data peak to one of two clusters. Aversive feedback from the monitors increased the proportion of short-duration, attenuated peaks from 38.8% to 96.6%. For each cluster, a distribution of parameters from a physics-based model of airborne particles is estimated. Peaks generated from these distributions are correctly identified by POD/clustering with >60% accuracy.

Feasibility and efficacy of an intervention to reduce secondhand smoke exposure among infants discharged from a neonatal intensive care unit.

OBJECTIVE: To examine the feasibility and efficacy of a hospital-based, motivational intervention to reduce secondhand smoke exposure (SHSe) with mothers of infants in a neonatal intensive care unit (NICU). STUDY DESIGN: One-hundred and forty-four mothers with infants ( ≤ 1500 g at birth or ≥ 12 h ventilation) in a NICU who reported a smoker in the household were randomized to two sessions of motivational interviewing (MI) conducted in the hospital, usual care (UC) or usual care-reduced measurement (UC-RM); follow-up occurred at 1- and 6-months post discharge. RESULT: For households that did not have a total smoking ban at baseline, 63.6% of those in the MI group instituted a ban by 1-month post discharge compared with 20% of the UC group, P<0.02. Six months post discharge, fewer smoking bans were noted in the UC-RM group relative to MI and UC, P<0.01. CONCLUSION: A need for SHSe interventions among NICU parents exists and initial evidence suggests MI can impact SHSe after discharge.

Evaluation of urinary trans-3'-hydroxycotinine as a biomarker of children's environmental tobacco smoke exposure.

The utility of urinary trans-3'-hydroxy cotinine (3HC) as a biomarker of environmental tobacco smoke (ETS) exposure was investigated in comparison with urinary cotinine (COT), the sum (3HC + COT), and ratio of the two nicotine metabolites (3HC/COT). Participants were 150 ETS exposed children (aged 1-44 months) and their parents. Child urine samples were collected during 3weekly baseline assessments and at interviews administered 3, 6, 12, and 18 months after baseline. Findings indicate that 3HC and COT can be measured reliably (rho = 0.96, 0.88) and show equivalent levels of repeated measures stability (rho = 0.71, 0.75). COT, 3HC, and 3HC + COT showed equally strong associations with air nicotine levels, reported ETS contamination, and reported ETS exposure (r=0.60-0.70). The intraclass correlations of 3HC/COT were lower than those for COT or 3HC. Older children had a higher 3HC/COT ratio than younger children (3.5 versus 2.2), and non-Hispanic White children had a higher ratio than African-American children (3.2 versus 1.9). These findings suggest that COT, 3HC, and 3HC + COT are approximately equivalent and equally strong biomarkers of ETS exposure in children. Moreover, 3HC/COT may provide a useful indicator to investigate age- and race-related differences in the metabolism of COT and 3HC.

Households contaminated by environmental tobacco smoke: sources of infant exposures.

OBJECTIVES: To examine (1) whether dust and surfaces in households of smokers are contaminated with environmental tobacco smoke (ETS); (2) whether smoking parents can protect their infants by smoking outside and away from the infant; and (3) whether contaminated dust, surfaces, and air contribute to ETS exposure in infants. DESIGN: Quasi-experiment comparing three types of households with infants: (1) non-smokers who believe they have protected their children from ETS; (2) smokers who believe they have protected their children from ETS; (3) smokers who expose their children to ETS. SETTING: Homes of smokers and non-smokers. PARTICIPANTS: Smoking and non-smoking mothers and their infants < or = 1 year. MAIN OUTCOME MEASURES: ETS contamination as measured by nicotine in household dust, indoor air, and household surfaces. ETS exposure as measured by cotinine levels in infant urine. RESULTS: ETS contamination and ETS exposure were 5-7 times higher in households of smokers trying to protect their infants by smoking outdoors than in households of non-smokers. ETS contamination and exposure were 3-8 times higher in households of smokers who exposed their infants to ETS by smoking indoors than in households of smokers trying to protect their children by smoking outdoors. CONCLUSIONS: Dust and surfaces in homes of smokers are contaminated with ETS. Infants of smokers are at risk of ETS exposure in their homes through dust, surfaces, and air. Smoking outside the home and away from the infant reduces but does not completely protect a smoker's home from ETS contamination and a smoker's infant from ETS exposure.

Intervention to reduce environmental tobacco smoke exposure in Latino children: null effects on hair biomarkers and parent reports.

OBJECTIVE: To evaluate the effectiveness of a lay delivered intervention to reduce Latino children's exposure to environmental tobacco smoke (ETS). The a priori hypothesis was that children living in households that were in the intervention group would have lower exposure over time than measurement only controls. DESIGN: A two group, randomised control trial was conducted. SETTING: Areas of San Diego county with a large Latino population. PARTICIPANTS: 143 Latino parent-child pairs. INTERVENTION: Trained bicultural and bilingual Latina lay community health advisors, or promotoras, conducted problem solving aimed at lowering the target child's exposure to ETS in the household. Six home and telephone sessions were delivered by the promotoras over a four month period. MAIN OUTCOME MEASURES: Outcome measures were collected at baseline, immediately post-intervention, three months post-intervention, and 12 months post-intervention. Four outcomes were considered: (1) parent's paper-and-pencil reports of the child's past month exposure; (2) hair samples from the child analysed for past month nicotine; (3) hair samples from the child analysed for past month cotinine; and (4) per cent confirmed reducers. RESULTS: There were no significant condition-by-time interactions, the term indicative of a differential intervention effect. Significant or near significant time main effects were seen for children's hair cotinine, per cent confirmed reducers, and, in particular, parent reports of exposure. CONCLUSIONS: Applying a lay promotora model to deliver the behavioural problem solving intervention unfortunately was not effective. A likely explanation relates to the difficulty of delivering a relatively complex intervention by lay women untrained in behaviour change theory and research methods.

Somatic complaints and isoniazid (INH) side effects in Latino adolescents with latent tuberculosis infection (LTBI).

This study examined the potential effects of INH side effects and non-specific somatic complaints on medication adherence in 96 Latino adolescents participating in a controlled trial designed to increase isoniazid (INH) adherence. These participants (who received usual medical care) were interviewed monthly over 9 months. Participants were questioned regarding medication taking, the frequency of 15 INH-related side effects from the Physician's Desk Reference (PDR) [1], and 21 non-specific somatic complaints. Participants were aged 12-19 years, 53.1% were male, 66.7% were born in Mexico, 73% had no health insurance, and 52.5% were classified as bicultural. Approximately 70% of participants experienced at least one side effect during the trial. Side effects that occurred while taking INH were not significantly related to total number of pills taken; somatic complaints that occurred during 9 months of INH were significantly negatively related to cumulative adherence. Females reported significantly more somatic complaints at baseline than males.

The feasibility and efficacy of tobacco use prevention in orthodontics.

SMILES PLUS was the first study to extend the clinician-delivered logic model to prevention of tobacco use among adolescents. This multi-site trial with 154 participating offices, based on social learning theory and a behavioral ecological model, was designed to test whether orthodontists can prevent preteens from initiating smoking. The study found that orthodontists do not automatically adhere to anti-tobacco prevention services. Social learning variables can enhance both adherence to counseling guidelines and content of counseling to increase prevention effects. Providing financial incentives, tracking prescriptions, prompting positive feedback from patients, and adopting anti-tobacco counseling models in the office are likely to enhance anti-tobacco preventive services. Training orthodontists to be comfortable when advising nonsmoking youth not to start and to use social consequences to justify youth avoidance of tobacco might increase adherence to protocols and make their counseling more powerful. Adolescent smokers prior to intervention were more likely to start other risky behaviors later. Preventing tobacco use may halt additional risk behaviors and thereby reduce morbidity/mortality even more than expected from tobacco control alone. New and refined clinical trials should be conducted to determine the most effective interventions for adolescent tobacco control by clinicians.

Observational assessment of family functioning at mealtime in preschool children with cystic fibrosis.

OBJECTIVE: To examine functioning during a dinner meal in families of a child with a chronic illness that requires dietary treatment recommendations, as compared to families of a child without a chronic illness. METHODS: Ratings of seven dimensions of family functioning on the McMaster Mealtime Family Interaction Coding System (MICS) were obtained on 29 families of children with CF and 29 families of children with no chronic illness, ages 2 to 6 years, during a videotaped dinner meal at home. RESULTS: Ratings of families with a child with CF were significantly lower than those for families of children without a chronic illness on Overall Family Functioning and five of the six MICS dimensions: Communication, Interpersonal Involvement, Affect Management, Behavior Control, and Role Allocation and approached significance on the Task Accomplishment dimension. The ratings of families of a child with CF were in the "clinically significant" range on all subcales, including Task ACCOMPLISHMENT. CONCLUSIONS: This study suggests that family functioning at mealtimes may be different in families of children with CF in which explicit dietary guidelines exist than in families of children with no illness or dietary guidelines. These results are discussed in terms of global family functioning and treatment approaches to dietary treatment recommendations.

Increasing asthma knowledge and changing home environments for Latino families with asthmatic children.

We tested an asthma education program in 204 underserved Latino families with an asthmatic child. The education program consisted of one or two sessions delivered in each family's home in the targeted participant's preferred language by a bilingual, bicultural educator. We encouraged, but did not require, attendance by the child. The curriculum was culturally-tailored, and all participants received education on understanding asthma, preventing asthma attacks, and managing asthma. Outcomes included change in asthma knowledge and change in home environment asthma management procedures. Asthma knowledge increased significantly (39 to 50% correct from pre- to post-test, P < 0.001) and participants made significant changes to the child's bedroom environment (mean number of triggers decreased from 2.4 to 1.8, P < 0.001; mean number of controllers increased from 0.7 to 0.9, P < 0.001). The results support the value of asthma education and its importance in the national agenda to reduce health disparities among minorities.

Tobacco use and other risk behaviors: cross-sectional and predictive relationships for adolescent orthodontic patients.

BACKGROUND: The purpose of these analyses was to examine the prevalence of selected substance abuse, general and dental health risk, and scholastic risk behaviors and their cross-sectional and predictive relationships with tobacco use among 15, 179 adolescent orthodontic patients in Southern California. METHODS: Subjects were recruited through 154 orthodontists' offices and interviewed by telephone at baseline and two-year posttest. RESULTS: Results show a pattern of increasing prevalence of risk behaviors with age. In most cases, gender differences were small. There were statistically significant positive relationships between each risk behavior and tobacco use status for both boys and girls. Prevalence rates of risk behaviors other than tobacco use were highest for current smokers, intermediate for experimenters, and lowest for respondents reporting that they had never used tobacco. Baseline tobacco use predicted each posttest risk behavior in logistic regression analyses. Principle components analysis (with varimax rotation) of posttest risk practices other than tobacco use yielded three theoretically meaningful factors, all which were predicted by baseline tobacco use in multiple regressions. CONCLUSIONS: These findings show that tobacco use among adolescents can predict subsequent risk practices other than tobacco use as long as two years, and that unhealthy behaviors among teens are interrelated. Orthodontists, who have a high frequency of adolescent patient contact, may be in a unique position to deliver health promotion interventions to their patients; possibly targeting multiple risk behaviors.

Reported measures of environmental tobacco smoke exposure: trials and tribulations.

OBJECTIVE: This report extends previous summaries of reported environmental tobacco smoke (ETS) exposure measures, reviews the empirical evidence of their validity for children's exposure, and discusses future research. DATA SOURCES: Studies were identified by computer search and from the authors' research. STUDY SELECTION: Studies were selected for inclusion of nicotine and/or cotinine and quantitative reported measures of ETS exposure. DATA SYNTHESIS: Five studies found significant associations between reported quantitative exposure of children to ETS and either environmental nicotine or urine cotinine assays. Correlation coefficients between parent reports and nicotine ranged from 0.22 to 0.75. Coefficients for cotinine ranged from 0.28 to 0.71. Correlations increased over time and were stronger for parents' reports of their own smoking as a source of children's exposure than for reports of exposure from others. CONCLUSIONS: Empirical studies show general concordance of reported and either environmental or biological measures of ETS exposure. Relationships were moderate, and suggest sufficient validity to be employed in research and service programs. Future studies need to identify the differences in types of reported or objective measures, population characteristics, etc, contributing to observed variability in order to understand better the conditions under which more valid reported ETS exposure and other measures can be obtained. Reported and either environmental or biological measures should be used in combination, and existing measures should be directed to interventions that may reduce ETS exposure among children.

Effect of counselling mothers on their children's exposure to environmental tobacco smoke: randomised controlled trial.

OBJECTIVE: To test the efficacy of behavioural counselling for smoking mothers in reducing young children's exposure to environmental tobacco smoke. DESIGN: Randomised double blind controlled trial. SETTING: Low income homes in San Diego county, California. PARTICIPANTS: 108 ethnically diverse mothers who exposed their children (aged <4 years) to tobacco smoke in the home. INTERVENTION: Mothers were given seven counselling sessions over three months. MAIN OUTCOME MEASURES: Children's reported exposure to environmental tobacco smoke from mothers in the home and from all sources; children's cotinine concentrations in urine. RESULTS: Mothers' reports of children's exposure to their smoke in the home declined in the counselled group from 27.30 cigarettes/week at baseline, to 4.47 at three months, to 3.66 at 12 months and in the controls from 24.56, to 12.08, to 8.38. The differences between the groups by time were significant (P=0.002). Reported exposure to smoke from all sources showed similar declines, with significant differences between groups by time (P=0.008). At 12 months, the reported exposure in the counselled group was 41.2% that of controls for mothers' smoke (95% confidence interval 34.2% to 48.3%) and was 45.7% (38.4% to 53.0%) that of controls for all sources of smoke. Children's mean urine cotinine concentrations decreased slightly in the counselled group from 10.93 ng/ml at baseline to 10.47 ng/ml at 12 months but increased in the controls from 9.43 ng/ml to 17.47 ng/ml (differences between groups by time P=0.008). At 12 months the cotinine concentration in the counselled group was 55.6% (48.2% to 63.0%) that of controls. CONCLUSIONS: Counselling was effective in reducing children's exposure to environmental tobacco smoke. Similar counselling in medical and social services might protect millions of children from environmental tobacco smoke in their homes.

Measuring secondhand smoke exposure in babies: the reliability and validity of mother reports in a sample of low-income families.

The reliability and validity of mother's reports of their infants' exposure to secondhand smoke (SHS) were examined in an ethnically diverse sample of low-income, low-education families (N = 141 mothers). At baseline and posttest, smoking mothers reported about their infants' SHS exposure at different locations and by different sources during the previous week. Findings show that mothers can give reliable accounts of the degree to which they contribute to their babies' SHS exposure. Mothers are able to differentiate between their own smoking behavior and the extent to which they expose their infants. Consistent with the overall exposure pattern, exposure caused by the mother and exposure occurring at home showed the strongest associations with biological and environmental measures. These findings suggest that smoking mothers can provide reliable and valid reports of the degree to which their infants are exposed to SHS.

Reducing children's exposure to environmental tobacco smoke: the empirical evidence and directions for future research.

OBJECTIVE: To summarise the issues and empirical evidence for reduction of children's residential environmental tobacco smoke (ETS) exposure. DATA SOURCES: Literature was obtained by computer search, with emphasis on studies that included quantitative measures of ETS exposure in children's residences and interventions based on social learning theory. STUDY SELECTION: Review and empirical articles concerning ETS exposure were included and inferences were drawn based on a synthesis of these studies as contrasted with a quantitative meta-analysis. DATA SYNTHESIS: Interventions designed for residential/child ETS exposure control have included policy/legal regulations, minimal clinical services, and counselling services. Divorce court and adoption services have limited custody to protect children from ETS exposure. Controlled trials of clinicians' one time counselling services have shown null results. One controlled trial found that repeated physician ETS counselling increased parent cessation. Three trials found that repeated counselling/shaping procedures reduced quantitative estimates of ETS exposure in asthmatic children. CONCLUSIONS: Insufficient controlled studies of repeated session counselling procedures have been completed to determine efficacy for ETS exposure reduction, but evidence is promising. One time minimal interventions appear ineffective, but large scale studies may be warranted. No studies have been conducted to assess court or adoption agency regulations; no community ordinances for regulating residential ETS exposure have been invoked. Ethical and enforcement issues are discussed.

Parent and child mealtime behavior in families of children with cystic fibrosis.

OBJECTIVES: We investigated the hypothesis that children with cystic fibrosis (CF) and their parents would show more maladaptive behaviors during dinner than children without CF and their parents. STUDY DESIGN: Children with CF (n = 32) and their parents were compared with 29 children without CF and their parents on the rate and frequency of parent-child behaviors during a typical dinner in the families' homes by using multivariate analyses of variance. RESULTS: When the rate of behavior, controlling for meal length, was examined, no differences were found between groups. However, parents of children with CF were found to differ from parents of control subjects in the frequency of direct and indirect commands (P <.05), coaxes (P <.01), physical prompts (P <.01), and feeding their child (P <.05). Children with CF were found to engage in more talk, spend more time away from the table, refuse food, and exhibit more noncompliance toward commands to eat than control children (P <.05 for all child variables). When behaviors were examined as a function of meal phase, parents of children with and without CF both showed an increase in commands (P <.01), coaxes (P <.05), feeds (P <.01), and physical prompts (P <.01) in the second half of the meal as compared with the first. Children with CF and the control children showed an increase in behaviors incompatible with eating during the second half of the meal compared with the first (P <.01). When faster eaters were compared with slower eaters, faster eaters consumed a higher percentage of the recommended daily allowance of energy (P <.01) than slower eaters and showed a trend to be at higher weight percentiles for age and sex (P =.08) regardless of group (CF or control). CONCLUSIONS: Children with CF and their parents do not differ from children without CF and their parents in the rate of behaviors exhibited or types of strategies used to encourage eating. However, children with CF and their parents engage in these behaviors more frequently. Our data do not support typical parenting behaviors as effective in meeting the CF dietary requirements. Additional support in the form of child behavior management training may be needed to assist parents in meeting their child's caloric requirements.

Involuntary smoking and asthma.

Involuntary smoking is the third leading preventable cause of death, and among children it causes lower respiratory infections, middle ear disease, sudden infant death syndrome, and asthma. Half the world's children may be exposed to environmental tobacco smoke (ETS), exacerbating symptoms in 20% of children with asthma. Recent studies have reinforced previous conclusions that ETS exposure causes onset of childhood asthma and exacerbation of symptoms throughout life. The exact mechanisms by which this is accomplished are still unclear, as are the relative contributions of prenatal versus postnatal exposure. However, favorable health outcomes can be attained with reduced exposure. Among the few studies of ETS exposure reduction interventions, low-intensity advice methods appeared ineffective, and counseling parent smokers appeared successful. Direct counseling of school-aged children to avoid ETS has yet to be tested. Community norms may need to shift further in favor of protecting children and others from ETS before minimal interventions can be successful. This will require combined and ongoing efforts of the medical and public health establishments, in concert with legislation mandating tobacco-free public places and with ETS-related media campaigns.

Measuring environmental tobacco smoke exposure in infants and young children through urine cotinine and memory-based parental reports: empirical findings and discussion.

OBJECTIVE: This study examined the reliability and potential biases of two urine collection methods from which cotinine measures were obtained and the validity of memory-based parental reports of their children's exposure to environmental tobacco smoke (ETS). DESIGN: Structured interviews were conducted with mothers of infants and young children to obtain memory-based estimates of recent ETS exposure. Urine samples were collected through standard and cotton roll collection methods for cotinine analysis. SETTING: All interviews took place at an off-campus research facility. Urine samples were collected at the study office or the subjects' homes. PARTICIPANTS: Mothers were recruited from San Diego county sites of the Women, Infants, and Children (WIC) Supplemental Food and Nutrition Program. Sample 1 (infants) consisted of eight boys and eight girls aged 1-44 months (mean = 12.6 months). Sample 2 (children) included 10 boys and 10 girls aged 3-8 years (mean = 61.2 months). MAIN OUTCOME MEASURES: Urine cotinine and memory-based parent reports of ETS exposure from structured interviews. RESULTS: There was overall high reliability for urine cotinine measures and no effect of collection method on urine cotinine levels. Memory-based reports obtained from smoking mothers showed moderately strong and consistent linear relationships with urine cotinine measures of their infants and children (r = 0.50 to r = 0.63), but not for reports obtained from non-smoking mothers. CONCLUSIONS: Memory-based parental reports of short-term ETS exposure can play an important role in quantifying ETS exposure in infants and children.