Biomedical subjects

Joel E Williams

Publications and source records attributed to Joel E Williams.

6 recordsLinked to original sources

PubMed2005

The Annual African American Conference on Diabetes: evolving program evaluation with evolving program implementation.

BACKGROUND: According to 2003 Behavioral Risk Factor Surveillance System data, South Carolina has the fourth highest rate of overall diabetes among the 50 states (9.3%) but the second highest rate among African Americans (15.5%). Nationwide, African Americans are disproportionately affected by diabetes. In addition, 40% of the African American population in South Carolina lives in a rural area, and approximately 26% live at or below the poverty level. Lack of access to health care and diabetes education are additional barriers for people with diabetes and their families. CONTEXT: Since 1997, the South Carolina Diabetes Prevention and Control Program and the Diabetes Today Advisory Council have sponsored the African American Conference on Diabetes, which targets African Americans with diabetes, their families, and their caregivers. This article describes the evolution of the conference and its evaluation. METHODS: In 2002, we conducted focus groups with 20 African American conference attendees with diabetes to 1) assess the program's effects, 2) determine how to reach more individuals, and 3) improve programming. In 2004, we incorporated the preconference and postconference Diabetes Understanding Scale survey to assess the cognitive impact of the conference on participants. CONSEQUENCES: Focus group results revealed that participants wanted to attend the conference because of the opportunity to increase their knowledge and change their behaviors through 1) education, 2) social support, 3) resources, and 4) logistics. Self-rated understanding increased significantly after the conference for each cognitive understanding item on the Diabetes Understanding Scale. INTERPRETATION: Focus group results suggested that participants who continue to attend the conference year after year may improve diabetes self-management skills. A quantitative evaluation showed that this 1-day diabetes education conference significantly increased short-term, self-rated cognitive understanding of diabetes behaviors.

Black or African American↗

PubMed2005

Development and use of a tool for assessing sidewalk maintenance as an environmental support of physical activity.

The importance of regular physical activity is well documented, yet according to epidemiological surveillance data, physical inactivity among all age groups persists. Past attempts to promote physical activity focused on individual-level changes; current approaches focus on environmental changes that will provide opportunities for whole communities to be active. The current ecological focus has led to an increase in funding and research regarding environmental supports of physical activity. As this is a new area of research, much work needs to be done to improve the ability to assess environmental features that support physical activity. This article describes a partnership between researchers and community members to develop and test an objective tool to measure sidewalk maintenance. Community members used data collected with the tool to increase awareness about sidewalk maintenance issues among local policy makers. Collaboration between researchers and community partners was critical for the success of this study.

Community-Institutional Relations↗

PubMed2004

Considerations for using a geographic information system to assess environmental supports for physical activity.

The use of a geographic information system (GIS) to study environmental supports for physical activity raises several issues, including acquisition and development, quality, and analysis. We recommend to public health professionals interested in using GIS that they investigate available data, plan for data development where none exists, ensure the availability of trained personnel and sufficient time, and consider issues such as data quality, analyses, and confidentiality. This article shares information about data-related issues that we encountered when using GIS to validate responses to a questionnaire about environmental supports for physical activity.

Crime↗

PubMed2004

Utility of pedometers for assessing physical activity: construct validity.

Valid assessment of physical activity is necessary to fully understand this important health-related behaviour for research, surveillance, intervention and evaluation purposes. This article is the second in a companion set exploring the validity of pedometer-assessed physical activity. The previous article published in Sports Medicine dealt with convergent validity (i.e. the extent to which an instrument's output is associated with that of other instruments intended to measure the same exposure of interest). The present focus is on construct validity. Construct validity is the extent to which the measurement corresponds with other measures of theoretically-related parameters. Construct validity is typically evaluated by correlational analysis, that is, the magnitude of concordance between two measures (e.g. pedometer-determined steps/day and a theoretically-related parameter such as age, anthropometric measures and fitness). A systematic literature review produced 29 articles published since > or =1980 directly relevant to construct validity of pedometers in relation to age, anthropometric measures and fitness. Reported correlations were combined and a median r-value was computed. Overall, there was a weak inverse relationship (median r = -0.21) between age and pedometer-determined physical activity. A weak inverse relationship was also apparent with both body mass index and percentage overweight (median r = -0.27 and r = -0.22, respectively). Positive relationships regarding indicators of fitness ranged from weak to moderate depending on the fitness measure utilised: 6-minute walk test (median r = 0.69), timed treadmill test (median r = 0.41) and estimated maximum oxygen uptake (median r = 0.22). Studies are warranted to assess the relationship of pedometer-determined physical activity with other important health-related outcomes including blood pressure and physiological parameters such as blood glucose and lipid profiles. The aggregated evidence of convergent validity (presented in the previous companion article) and construct validity herein provides support for considering simple and inexpensive pedometers in both research and practice.

Adolescent↗

PubMed2003

Environmental measures of physical activity supports: perception versus reality.

BACKGROUND: Perceptions of the environment and physical activity have been associated using survey methods, yet little is known about the validity of environmental surveys. In this study, perceptions of the environment at neighborhood and community levels were assessed (1) to determine validity by comparing respondent perceptions to objective measures and (2) to determine test-retest reliability of the survey. METHODS: A telephone survey was administered to a stratified sample of Sumter County, South Carolina adults. Respondents' home addresses were mapped using a geographic information system (GIS) (n =1112). As an indicator of validity, kappa statistics were used to measure agreement between perceptions and objective measures identified at neighborhood and community levels using GIS. A second survey in an independent sample (n=408) assessed test-retest reliability. RESULTS: When assessing perceptions of environmental and physical activity in a defined geographic area, validity and reliability for neighborhood survey items were kappa= -0.02 to 0.37 and rho=0.42 to 0.74, and for community survey items were kappa= -0.07 to 0.25 and rho=0.28 to 0.56. CONCLUSIONS: Although causality between perception of access and safety and actual physical activity level cannot be assumed, those meeting national physical activity guidelines or reporting some physical activity demonstrated greatest agreement with access to recreation facilities, while those not meeting the guidelines demonstrated greater agreement with safety of recreation facilities. Factors such as distance and behavior may explain differences in perceptions at neighborhood and community levels. Using local environments with short distances in survey methods improves validity and reliability of results.

Adult↗

PubMed2002

Utility of pedometers for assessing physical activity: convergent validity.

Valid assessment of physical activity is important to researchers and practitioners interested in surveillance, screening, programme evaluation and intervention. The validity of an assessment instrument is commonly considered its most important attribute. Convergent validity is the extent to which an instrument's output is associated with that of other instruments intended to measure the same exposure of interest. A systematic review of the literature produced 25 articles directly relevant to the question of convergent validity of pedometers against accelerometers, observation, and self-reported measures of physical activity. Reported correlations were pooled and a median r-value was computed. Pedometers correlate strongly (median r = 0.86) with different accelerometers (specifically uniaxial accelerometers) depending on the specific instruments used, monitoring frame and conditions implemented, and the manner in which the outputs are expressed. Pedometers also correlate strongly (median r = 0.82) with time in observed activity. Time in observed inactivity correlated negatively with pedometer outputs (median r = -0.44). The relationship with observed steps taken depended upon monitoring conditions and speed of walking. The highest agreement was apparent during ambulatory activity (running, walking) or during sitting (when both observation and pedometers would register few steps taken). There was consistent evidence of reduced accuracy during slow walking. Pedometers correlate moderately with different measures of energy expenditure (median r = 0.68). The relationship between pedometer outputs and energy expenditure is complicated by the use of many different direct and indirect measures of energy expenditure and population samples. Concordance with self-reported physical activity (median r = 0.33) varied depending upon the self-report instrument used, individuals assessed, and how pedometer outputs are expressed (e.g. steps, distance travelled, energy expenditure). Pedometer output has an inverse relationship with reported time spent sitting (r = -0.38). The accumulated evidence herein provides ample support that the simple and inexpensive pedometer is a valid option for assessing physical activity in research and practice.

Activities of Daily Living↗