Nicotine gum use and outcome in a general practitioner intervention against smoking.

In a general practitioner intervention against smoking (employing nicotine chewing gum) smokers who used more than a box of gum were, prior to the intervention, more motivated to quit smoking and more dependent than those who did not use more than a box. They were also older. Even after controlling for demographic, dependence, motivational and previous success factors, those who used more than a box of gum had a significantly enhanced probability of success compared with other smokers. Although causal conclusions cannot be drawn from these analyses, stress on the importance of persistence in use of the gum is recommended.

District programme to reduce smoking: can sustained intervention by general practitioners affect prevalence?

A total of 101 general practitioners in 27 practices in inner London took part in a quasi-experimental study designed to examine whether a brief intervention applied to all smokers seen by general practitioners and sustained on a continuous basis could in time have a cumulative effect and reduce the prevalence of smoking among their patients. Of 21 practices approached in our local district (Camberwell), seven were willing to undertake brief intervention with support from the smokers' clinic (SBI), four opted for intervention without support (BI), and six acted as usual care controls. A further 10 out of 12 practices approached in South Hammersmith provided an unselected group of usual care controls. A series of six cross-sectional surveys were conducted over a three-year period. Each survey consisted of all adult patients attending to see a doctor during a defined two-week period, sample sizes averaging just over 9000 per survey. The estimated decline in self-reported smoking prevalence over the 30-month period following the start of intervention was 5.5% (from 36.4% to 30.9%) in the SBI group compared with 2.1% for BI and 2.8% and 3.0% in the two usual care control groups, the decline in the SBI group being significantly greater than in the other groups which did not differ significantly between each other. These interim results provide encouraging evidence that brief intervention by general practitioners with support and back-up from a local smokers' clinic can, when sustained on a continuous basis, reach sufficient smokers to reduce smoking prevalence in their practice populations. However, firm conclusions must await longer periods of observation now that the other Camberwell practices have adopted the SBI procedures.

District programme to reduce smoking: effect of clinic supported brief intervention by general practitioners.

By encouraging and supporting general practitioners to undertake brief intervention on a routine basis smokers' clinics could reach many more smokers than are willing to attend for intensive treatment. In a study with 101 general practitioners from 27 practices 4445 cigarette smokers received brief intervention with the support of a smokers' clinic, brief intervention without such support, or the general practitioners' usual care. At one year follow up the numbers of smokers who reported that they were no longer smoking cigarettes were 51 (13%), 63 (9%), and 263 (8%), respectively (p less than 0.005). After an adjustment was made for those cases not validated by urine cotinine concentrations the respective success rates were 8%, 5%, and 5%. Use of nicotine chewing gum was associated with higher self reported success rates. General practitioners providing supported brief intervention encouraged not only more smokers to use the gum but also more effective use; gum users in this group reported a success rate of 27% at one year. Compliance by the general practitioners in recording smoking state averaged 45%, and significantly higher success rates were reported by patients whose smoking state had been recorded. Brief intervention by general practitioners with the support of a smokers' clinic thus significantly enhanced success rates based on self reports. Better results might be obtained if general practitioners' compliance with the procedure could be improved and if they encouraged more of their patients to try nicotine gum. Collaboration of this kind between a smokers' clinic and local general practitioners could deliver effective help to many more smokers than are likely to be affected if the two continue to work separately.

Predictors of outcome in a general practitioner intervention against smoking.

Analysis of baseline population characteristics in a large-scale (N = 1,328), controlled trial of general practitioner intervention against smoking (including advice and advice plus nicotine gum groups) revealed significant associations between the probability of abstinence at 4 months and sex, longest previous abstinence, dependence, motivation to quit smoking, and cigarette consumption. Women did less well overall, and dependence had a greater negative relationship to outcome among women than among men. The positive association of motivation was greater for higher levels of cigarette consumption. In the nicotine gum group, the negative dependence relationship was smaller than that in the other two groups (advice and control). Longest previous abstinence had a curvilinear relationship to outcome, the positive association diminishing as length of abstinence increased. Notwithstanding the above interactions, the gum offer was universally beneficial, except at the lowest levels of dependence, where it had little effect.

Digital image processing of cephalometric radiographs: a preliminary report.

The principles of image capture, image storage and image processing in digital radiology are described. The enhancement of radiographic images using digital image processing techniques and its application to cephalometry is discussed. The results of a pilot study which compared some common cephalometric measurements made from manual point identification with those made by direct digitization of digital radiographic images from video monitors are presented. Although in an early stage of development, the results from the image processing system were comparable with those obtained by traditional methods.

Brain and ventricular volume in hydrocephalus.

A study is presented based on CT scans, using advanced computer techniques, to determine brain volume in a representative sample of sixteen subjects, with treated and untreated hydrocephalus, whose ventricle size varied from normal to extreme and from symmetrical to grossly asymmetrical dilatation. The calculations take into account the maximal head circumference at the time of the CT scans and the results are correlated with the patients' intellectual and neurological conditions.