Gregory J. Norman

A Text Message-Based Intervention for Weight Loss: Randomized Controlled Trial

Background To our knowledge, no studies have evaluated whether weight loss can be promoted in overweight adults through the use of an intervention that is largely based on daily SMS (Short Message Service: text) and MMS (Multimedia Message Service: small picture) messages transmitted via mobile phones. Objective This paper describes the development and evaluation of a text message–based intervention designed to help individuals lose or maintain weight over 4 months. Methods The study was a randomized controlled trial, with participants being exposed to one of the following two conditions, lasting 16 weeks: (1) receipt of monthly printed materials about weight control; (2) an intervention that included personalized SMS and MMS messages sent two to five times daily, printed materials, and brief monthly phone calls from a health counselor. The primary outcome was weight at the end of the intervention. A mixed-model repeated-measures analysis compared the effect of the intervention group to the comparison group on weight status over the 4-month intervention period. Analysis of covariance (ANCOVA) models examined weight change between baseline and 4 months after adjusting for baseline weight, sex, and age. Results A total of 75 overweight men and women were randomized into one of the two groups, and 65 signed the consent form, completed the baseline questionnaire, and were included in the analysis. At the end of 4 months, the intervention group (n = 33) lost more weight than the comparison group (−1.97 kg difference, 95% CI −0.34 to −3.60 kg, P = .02) after adjusting for sex and age. Intervention participants’ adjusted average weight loss was 2.88 kg (3.16%). At the end of the study, 22 of 24 (92%) intervention participants stated that they would recommend the intervention for weight control to friends and family. Conclusions Text messages might prove to be a productive channel of communication to promote behaviors that support weight loss in overweight adults. Trial Registration Clinicaltrials.gov NCT00415870; http://clinicaltrials.gov/ct2/show/NCT00415870 (Archived by WebCite at http://www.webcitation.org/5dnolbkFt)

SAFETY Study: Alanine Aminotransferase Cutoff Values Are Set Too High for Reliable Detection of Pediatric Chronic Liver Disease

BACKGROUND & AIMS The appropriate alanine aminotransferase (ALT) threshold value to use for diagnosis of chronic liver disease in children is unknown. We sought to develop gender-specific, biology-based, pediatric ALT thresholds. METHODS The Screening ALT for Elevation in Todays Youth (SAFETY) study collected observational data from acute care childrens hospitals, the National Health and Nutrition Examination Survey (NHANES, 1999-2006), overweight children with and without non-alcoholic fatty liver disease (NAFLD), and children with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. The study compared the sensitivity and specificity of ALT thresholds currently used by childrens hospitals vs study-derived, gender-specific, biology-based, ALT thresholds for detecting children with NAFLD, HCV, or HBV. RESULTS The median upper limit of ALT at childrens hospitals was 53 U/L (range, 30-90 U/L). The 95th percentile levels for ALT in healthy weight, metabolically normal, liver disease-free, NHANES pediatric participants were 25.8 U/L (boys) and 22.1 U/L (girls). The concordance statistics of these NHANES-derived thresholds for liver disease detection were 0.85 (95% confidence interval [CI]: 0.74-0.96) in boys and 0.91 (95% CI: 0.83-0.99) in girls for NAFLD, 0.80 (95% CI: 0.70-0.91) in boys and 0.79 (95% CI: 0.69-0.89) in girls for HBV, and 0.86 (95% CI: 0.77-0.95) in boys and 0.84 (95% CI: 0.75-0.93) in girls for HCV. Using current childrens hospitals ALT thresholds, the median sensitivity for detection of NAFLD, HBV, and HCV ranged from 32% to 48%; median specificity was 92% (boys) and 96% (girls). Using NHANES-derived thresholds, the sensitivities were 72% (boys) and 82% (girls); specificities were 79% (boys) and 85% (girls). CONCLUSIONS The upper limit of ALT used in childrens hospitals varies widely and is set too high to reliably detect chronic liver disease. Biology-based thresholds provide higher sensitivity and only slightly less specificity. Clinical guidelines for use of screening ALT and exclusion criteria for clinical trials should be modified.

Psychosocial and Environmental Correlates of Adolescent Sedentary Behaviors

Objective. To determine correlates of sedentary behaviors in adolescents through the examination of psychosocial and environmental variables. Method. The study used a cross-sectional design to evaluate an ethnically diverse clinic-based sample of 878 adolescents who were 11 to 15 years old. Bivariate and multivariate analyses were stratified by gender to assess correlates of sedentary behaviors occurring on the most recent nonschool day (television viewing, computer video games, sitting listening to music, and talking on the phone). Results. For girls, age, family support, television/video rules, and hills in the neighborhood were associated with sedentary behaviors. Furthermore, psychological constructs such as self-efficacy, enjoyment, change strategies, and pros and cons of change emerged as correlates of sedentary behaviors. A moderator effect revealed that the proportion of girls in the low-BMI group decreased with increased self-efficacy, whereas the proportion of girls in the high-BMI group did not vary significantly by self-efficacy. For boys, age, ethnicity, BMI, cons of change, and self-efficacy were associated with sedentary behaviors. Conclusions. This study provides evidence of factors associated and not associated with adolescent sedentary behaviors. Similar to physical activity, measures of specific psychosocial constructs of sedentary behavior demonstrated important associations. The results highlight the need for additional examination of the correlates of sedentary behavior to determine which correlates are mechanisms of behavior change.

Neighborhood Environment Walkability Scale for Youth (NEWS-Y): Reliability and Relationship With Physical Activity

OBJECTIVES To examine the psychometric properties of the Neighborhood Environment Walkability Scale-Youth (NEWS-Y) and explore its associations with context-specific and overall physical activity (PA) among youth. METHODS In 2005, parents of children ages 5-11 (n=116), parents of adolescents ages 12-18 (n=171), and adolescents ages 12-18 (n=171) from Boston, Cincinnati, and San Diego, completed NEWS-Y surveys regarding perceived land use mix-diversity, recreation facility availability, pedestrian/automobile traffic safety, crime safety, aesthetics, walking/cycling facilities, street connectivity, land use mix-access, and residential density. A standardized neighborhood environment score was derived. Self-reported activity in the street and in parks, and walking to parks, shops, school, and overall physical activity were assessed. RESULTS The NEWS-Y subscales had acceptable test-retest reliability (ICC range .56-.87). Being active in a park, walking to a park, walking to shops, and walking to school were related to multiple environmental attributes in all three participant groups. Total neighborhood environment, recreation facilities, walking and cycling facilities, and land use mix-access had the most consistent relationships with specific types of activity. CONCLUSIONS The NEWS-Y has acceptable reliability and subscales were significantly correlated with specific types of youth PA. The NEWS-Y can be used to examine neighborhood environment correlates of youth PA.

TESTING 40 PREDICTIONS FROM THE TRANSTHEORETICAL MODEL

Sensitive measurement of behavior change requires dependent measures that are sensitive to the whole spectrum of change, not just a single aspect of change. Traditional outcome variables such as point prevalence for smoking cessation focus on a single discrete event and ignore all other progress. Alternatively, the criterion measurement model (CMM) is an approach that posits a three-construct outcome model (habit strength, positive evaluation strength, and negative evaluation strength), where different constructs are sensitive to change for different aspects of the temporal domain. In this article, a series of 40 differential a priori predictions were tested using a large representative sample of smokers. The focus was on the prediction of specific effect sizes rather than statistical significance. A series of comparisons involving stage transitions was examined using five variables representing the three CMM constructs. The predictions involved movement from one of three initial stages (precontemplation, contemplation, and preparation) to stage membership 12 months later. Thirty-six of the 40 predictions were confirmed, indicating that the outcome model has strong construct validity and accurately reflects movement between the stages of change.

A lifestyle intervention for older schizophrenia patients with diabetes mellitus: A randomized controlled trial ☆

PURPOSE We tested the feasibility and preliminary efficacy of a lifestyle intervention for middle-aged and older patients with schizophrenia and type-2 diabetes mellitus, using a randomized pre-test, post-test control group design. METHOD Individuals with a diagnosis of schizophrenia or schizoaffective disorder over the age of 40 were randomly assigned to 24-week Diabetes Awareness and Rehabilitation Training (DART; n=32) groups or Usual Care plus Information (UCI; n=32) comparison groups. Participants were recruited from board-and-care facilities and day treatment programs. Fifty-seven patients completed baseline and 6-month assessments consisting of an interview, measures of body mass index, blood pressure, fasting blood chemistry, and accelerometry. A mixed-model analysis of variance was used to analyze the data. RESULTS A significant group x time interaction was found for body weight, with patients in the DART group losing a mean of 5 lb and those in the UCI gaining a mean 6 lb. Significant group x time interactions were also found for triglycerides, diabetes knowledge, diabetes self-efficacy, and self-reported physical activity, but not for fasting plasma glucose or glycosylated hemoglobin. CONCLUSIONS Group-based lifestyle interventions are feasible and produce positive health changes in middle-aged and older patients with schizophrenia and diabetes mellitus.

Classification Accuracies of Physical Activities Using Smartphone Motion Sensors

Background Over the past few years, the world has witnessed an unprecedented growth in smartphone use. With sensors such as accelerometers and gyroscopes on board, smartphones have the potential to enhance our understanding of health behavior, in particular physical activity or the lack thereof. However, reliable and valid activity measurement using only a smartphone in situ has not been realized. Objective To examine the validity of the iPod Touch (Apple, Inc.) and particularly to understand the value of using gyroscopes for classifying types of physical activity, with the goal of creating a measurement and feedback system that easily integrates into individuals’ daily living. Methods We collected accelerometer and gyroscope data for 16 participants on 13 activities with an iPod Touch, a device that has essentially the same sensors and computing platform as an iPhone. The 13 activities were sitting, walking, jogging, and going upstairs and downstairs at different paces. We extracted time and frequency features, including mean and variance of acceleration and gyroscope on each axis, vector magnitude of acceleration, and fast Fourier transform magnitude for each axis of acceleration. Different classifiers were compared using the Waikato Environment for Knowledge Analysis (WEKA) toolkit, including C4.5 (J48) decision tree, multilayer perception, naive Bayes, logistic, k-nearest neighbor (kNN), and meta-algorithms such as boosting and bagging. The 10-fold cross-validation protocol was used. Results Overall, the kNN classifier achieved the best accuracies: 52.3%–79.4% for up and down stair walking, 91.7% for jogging, 90.1%–94.1% for walking on a level ground, and 100% for sitting. A 2-second sliding window size with a 1-second overlap worked the best. Adding gyroscope measurements proved to be more beneficial than relying solely on accelerometer readings for all activities (with improvement ranging from 3.1% to 13.4%). Conclusions Common categories of physical activity and sedentary behavior (walking, jogging, and sitting) can be recognized with high accuracies using both the accelerometer and gyroscope onboard the iPod touch or iPhone. This suggests the potential of developing just-in-time classification and feedback tools on smartphones.

Assessment of Physical Activity in Middle-aged and Older Adults with Schizophrenia

BACKGROUND Regular physical activity (PA) decreases morbidity in the general population; yet, information about the amount and effects of PA in persons with schizophrenia is scant. To develop interventions to increase PA and to assess its potential benefits in this group, accurate measurement of PA is needed. The purpose of this study was to characterize PA and determine the test-retest reliability and concurrent validity of the Yale Physical Activity Scale (YPAS), a self-report measure, in persons with schizophrenia. METHODS PA was assessed with the YPAS, a scale of motivational readiness for PA, and accelerometry in middle-aged and older persons with a diagnosis of schizophrenia (n=54) and in a comparison group with no known psychiatric diagnosis (n=27). RESULTS On the YPAS measures, persons with schizophrenia reported on average 11 h per week of PA, whereas the non-psychiatric comparison group reported about 32 h per week. Only about 30% of schizophrenia subjects were classified as being regularly active relative to 62% of the comparison group on PA motivational stages of readiness. On the accelerometry measures, the schizophrenia group had lower levels of light activity than the comparison group, but there were no differences in moderate and vigorous activity or sedentary behavior. Only in the comparison group were there significant associations between YPAS and accelerometer variables. Several YPAS scores demonstrated high test-retest reliability in both groups, and concurrent validity was supported between the YPAS and PA motivational stages of readiness. CONCLUSIONS We found that the YPAS is a reliable measure of PA in schizophrenia for some indices. Although the YPAS demonstrated concurrent validity with other self-report measures, it did not demonstrate concurrent validity when compared to PA measured by accelerometry in persons with schizophrenia. Use of multiple measures, both subjective and objective, is recommended when assessing PA in schizophrenia.

Community Food Environment, Home Food Environment, and Fruit and Vegetable Intake of Children and Adolescents

OBJECTIVES To determine (1) reliability of new food environment measures; (2) association between home food environment and fruit and vegetable (FV) intake; and (3) association between community and home food environment. METHODS In 2005, a cross-sectional survey was conducted with readministration to assess test-retest reliability. Adolescents, parents of adolescents, and parents of children (n = 458) were surveyed in San Diego, Boston, and Cincinnati. RESULTS Most subscales had acceptable reliability. Fruit and vegetable intake was positively associated with availability of healthful food (r = 0.15-0.27), FV (r = 0.22-0.34), and ratio of more-healthful/less-healthful food in the home (r = 0.23-0.31) and was negatively associated with less-healthful food in the home (r = -0.17 to -0.18). Home food environment was associated with household income but not with community food environment. CONCLUSIONS AND IMPLICATIONS A more healthful home food environment was related to youth FV intake. Higher income households had more healthful food in the home. The potential influence of neighborhood food outlets warrants further study.

The development of a stress survey schedule for persons with autism and other developmental disabilities.

The Stress Survey Schedule is an instrument for measuring stress in the lives of persons with autism and other developmental disabilities. Development of the survey and analysis of the underlying measurement structure of the instrument is reported in three studies. Through the use of exploratory and confirmatory analysis procedures, eight dimensions of stress were identified: Anticipation/Uncertainty, Changes and Threats, Unpleasant Events, Pleasant Events, Sensory/Personal Contact, Food Related Activity, Social/Environmental Interactions, and Ritual Related Stress. These stress dimensions are highly relevant to the problems of autism and have not been addressed by other stress surveys. The information obtained from the Stress Survey can be used to plan for strategies to reduce the stress before it occurs or results in maladaptive behavior.