The Stanford Leisure-Time Activity Categorical Item (L-Cat): a single categorical item sensitive to physical activity changes in overweight/obese women

Stanford Prevention Research Center, Stanford School of Medicine, Stanford, CA, USA.
International journal of obesity (2005) (Impact Factor: 5). 04/2013; 37(12). DOI: 10.1038/ijo.2013.36
Source: PubMed


Physical activity is essential for chronic disease prevention, yet <40% of overweight/obese adults meet the national activity recommendations. For time-efficient counseling, clinicians need a brief, easy-to-use tool that reliably and validly assesses a full range of activity levels, and, most importantly, is sensitive to clinically meaningful changes in activity. The Stanford Leisure-Time Activity Categorical Item (L-Cat) is a single item comprising six descriptive categories ranging from inactive to very active. This novel methodological approach assesses national activity recommendations as well as multiple clinically relevant categories below and above the recommendations, and incorporates critical methodological principles that enhance psychometrics (reliability, validity and sensitivity to change).

We evaluated the L-Cat's psychometrics among 267 overweight/obese women who were asked to meet the national activity recommendations in a randomized behavioral weight-loss trial.

The L-Cat had excellent test-retest reliability (κ=0.64, P<0.001) and adequate concurrent criterion validity; each L-Cat category at 6 months was associated with 1059 more daily pedometer steps (95% CI 712-1407, β=0.38, P<0.001) and 1.9% greater initial weight loss at 6 months (95% CI -2.4 to -1.3, β=-0.38, P<0.001). Of interest, L-Cat categories differentiated from each other in a dose-response gradient for steps and weight loss (Ps<0.05) with excellent face validity. The L-Cat was sensitive to change in response to the trial's activity component. Women increased one L-Cat category at 6 months (M=1.0±1.4, P<0.001); 55.8% met the recommendations at 6 months whereas 20.6% did at baseline (P<0.001). Even among women not meeting the recommendations at both baseline and 6 months (n=106), women who moved 1 L-Cat categories at 6 months lost more weight than those who did not (M=-4.6%, 95% CI -6.7 to -2.5, P<0.001).

Given strong psychometrics, the L-Cat has timely potential for clinical use such as tracking activity changes via electronic medical records, especially among overweight/obese populations who are unable or unlikely to reach national recommendations.

Download full-text


Available from: Michael G Perri, Nov 13, 2014
45 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Brief, valid, and reliable dietary and physical activity assessment tools are needed, and interactive computerized assessments (ie, those with visual cues, pictures, sounds, and voiceovers) can reduce administration and scoring burdens commonly encountered with paper-based assessments. The purpose of this pilot investigation was to evaluate the comparative validity and reliability of interactive multimedia (IMM) versions (ie, IMM-1 and IMM-2) compared to validated paper-administered (PP) versions of the beverage intake questionnaire (BEVQ-15) and Stanford Leisure-Time Activity Categorical Item (L-Cat); a secondary purpose was to evaluate results across two education attainment levels. Adults 21 years or older (n=60) were recruited to complete three laboratory sessions, separated by three to seven days in a randomly assigned sequence, with the following assessments-demographic information, two IMM and one paper-based (PP) version of the BEVQ-15 and L-Cat, health literacy, and an IMM usability survey. Responses across beverage categories from the IMM-1 and PP versions (validity; r=.34-.98) and the IMM-1 and IMM-2 administrations (reliability; r=.61-.94) (all P<.001) were significantly correlated. Paired t tests revealed significant differences in sugar-sweetened beverage (SSB) grams and kcal (P=.02 and P=.01, respectively) and total beverage kcal (P=.03), on IMM-1 and IMM-2; however, comparative validity was demonstrated between IMM-2 and the PP version suggesting familiarization with the IMM tool may influence participant responses (mean differences: SSB 63 grams, SEM 87; P=.52; SSB 21 kcal, SEM 33; P=.48; total beverage 65 kcal, SEM 49; P=.19). Overall mean scores between the PP and both IMM versions of the L-Cat were different (both P<.001); however, responses on all versions were correlated (P<.001). Differences between education categories were noted at each L-Cat administration (IMM-1: P=.008; IMM-2: P=.001; PP: P=.002). Major and minor themes from user feedback suggest that the IMM questionnaires were easy to complete, and relevant to participants' typical beverage choices and physical activity habits. In general, less educated participants consumed more total beverage and SSB energy, and reported less engagement in physical activity. The IMM BEVQ-15 appears to be a valid and reliable measure to assess habitual beverage intake, although software familiarization may increase response accuracy. The IMM-L-Cat can be considered reliable and may have permitted respondents to more freely disclose actual physical activity levels versus the paper-administered tool. Future larger-scale investigations are warranted to confirm these possibilities.
    10/2013; 2(2):e40. DOI:10.2196/resprot.2830
  • [Show abstract] [Hide abstract]
    ABSTRACT: High consumption of sugar-sweetened beverages (SSB) contributes to a wide range of poor health outcomes. Further, few US adults drink less than the recommended ≤8 ounces per day; and individuals with low socioeconomic, low health literacy status, and in rural areas are even less likely to meet recommendations. Unfortunately, few SSB behavioral interventions exist targeting adults, and none focus on low health literacy in rural areas. Talking Health, a type 1 effectiveness-implementation hybrid trial targeting adults in rural southwest Virginia, was developed using the RE-AIM planning and evaluation framework (reach, effectiveness, adoption, implementation, maintenance). The primary aim of this pragmatic randomized-controlled trial was to determine the effectiveness of a scalable 6-month intervention aimed at decreasing SSB consumption (SIPsmartER) when compared to a matched contact physical activity promotion control group (MoveMore). SIPsmartER was developed based upon the Theory of Planned Behavior and uses health literacy strategies to improve comprehension of the intervention content among participants. MoveMore is based on a research-tested intervention that was adapted to address all theory of planned behavior constructs and health literacy principles. Secondary aims include additional health outcomes (e.g., physical activity, weight) and reach, adoption, implementation, and maintenance indicators. This paper highlights the opportunities and considerations for developing health behavior trials that aim to determine intervention effectiveness, provide all study participants an opportunity to benefit from research participation, and collect key information on reach and the potential for organizational adoption, implementation, and maintenance with the longer-term goal of speeding translation into practice settings.
    Contemporary clinical trials 11/2013; 37(1). DOI:10.1016/j.cct.2013.11.003 · 1.94 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Telomere length, a reliable predictor of disease pathogenesis, can be affected by genetics, chronic stress and health behaviors. Cross-sectionally, highly stressed postmenopausal women have shorter telomeres, but only if they are inactive. However, no studies have prospectively examined telomere length change over a short period, and if rate of attrition is affected by naturalistic factors such as stress and engagement in healthy behaviors, including diet, exercise, and sleep. Here we followed healthy women over 1 year to test if major stressors that occurred over the year predicted telomere shortening, and whether engaging in healthy behaviors during this period mitigates this effect. In 239 postmenopausal, non-smoking, disease-free women, accumulation of major life stressors across a 1-year period predicted telomere attrition over the same period-for every major life stressor that occurred during the year, there was a significantly greater decline in telomere length over the year of 35 bp (P<0.05). Yet, these effects were moderated by health behaviors (interaction B=0.19, P=0.04). Women who maintained relatively higher levels of health behaviors (1 s.d. above the mean) appeared to be protected when exposed to stress. This finding has implications for understanding malleability of telomere length, as well as expectations for possible intervention effects. This is the first study to identify predictors of telomere length change over the short period of a year.Molecular Psychiatry advance online publication, 29 July 2014; doi:10.1038/mp.2014.70.
    Molecular Psychiatry 07/2014; 20(4). DOI:10.1038/mp.2014.70 · 14.50 Impact Factor