Peer influence and selection processes in adolescent smoking behavior: a comparative study.

INTRODUCTION: Adolescent smoking studies find evidence of active peer influence and selection processes. However, studies have shown that these processes operate differently depending on context. This study uses SIENA to model coevolutionary processes between smoking and changes in friendship ties, comparing two high schools in which data were collected in identical fashion to explore influence and selection mechanisms with respect to current smoking, and smoking levels. METHODS: This is a longitudinal survey with 2 waves of data. In-home surveys were conducted with students from 2 large high schools in the United States: a West Coast school, and a Midwestern school. Participants were consented students in 10th and 11th grades at the first wave of data collection. The primary measures were self-reported smoking behavior and friendship nominations. RESULTS: There is evidence of influence and selection in both schools for adolescents' smoking status (1 = any smoking) and for level of smoking. CONCLUSIONS: These models reflect great similarities in influence and selection processes across schools for different smoking behaviors. However, smoking prevalence may impact the exact mechanisms by which influence and selection operate. Researchers should consider smoking interventions with independent modules addressing different selection and influence processes, implemented based on contextual factors such as the prevalence of smoking.

Electronic records suggest suboptimal management of chronic kidney disease in general practice.

OBJECTIVE: To examine electronic records of GP management of chronic kidney disease. DESIGN: Cross-sectional study. SETTING: Thirteen general practices. PARTICIPANTS: Fifteen thousand four hundred and fiftteen active patients aged 50 years and over. MAIN OUTCOME MEASURE: Recorded estimated glomerular filtration rate (eGFR) and diabetes, and rate of prescribing of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACE/ARBs). RESULTS: Six thousand and fifty-nine (39%) patients had hypertension and 1859 (12%), diabetes. Two thousand six hundred and eighty-nine (17%) patients were recorded with eGFR < 60 mL min(-1) (1.73 m(2) )(-1) , while 3344 (22%) did not have an eGFR result recorded. Hypertension, diabetes and eGFR <60 mL min(-1) (1.73 m(2) )(-1 ) were shown to be significantly related to prescribing of ACE/ARBs; however, 31% of known diabetics and 23% of diabetics with an eGFR < 60 mL min(-1) (1.73 m(2) )(-1 ) are not recorded as receiving ACE or ARB therapy. Forty-two per cent of patients with eGFR < 60 mL min(-1) (1.73 m(2) )(-1) , are also not recorded as receiving ACE or ARB therapy. There was a 23% variation in the rates of prescribing of ACE/ARBs by practice for patients with diabetes and eGFR < 60 mL min(-1) (1.73 m(2) )(-1) . CONCLUSION: The overall recording of eGFR and the recorded prescribing of ACE or ARB therapy in known diabetics and patients with eGFR < 60 mL min(-1) (1.73 m(2) )(-1) appear suboptimal. Also, the variations in prescribing between practices require further investigation.