Does self-control modify the impact of interventions to change alcohol, tobacco, and food consumption? A systematic review.

Low self-control is associated with increased consumption of alcohol, tobacco, and unhealthy food. This systematic review aimed to assess whether individual differences in self-control modify the effectiveness of interventions to reduce consumption of these products, and hence their potential to reduce consumption amongst those whose consumption is generally greater. Searches of six databases were supplemented with snowball searches and forward citation tracking. Narrative synthesis summarised findings by: consumption behaviour (alcohol, tobacco, food); psychological processes targeted by the intervention (reflective, non-reflective, or both); and study design (experiment, cohort, or cross-sectional). Of 54 eligible studies, 22 reported no evidence of modification, 18 reported interventions to be less effective in those with low self-control, and 14 reported interventions to be more effective in those with low self-control. This pattern did not differ from chance. Whilst self-control often influenced intervention outcomes, there was no consistent pattern of effects, even when stratifying studies by consumption behaviour, intervention type, or study design. There was a notable absence of evidence regarding interventions that restructure physical or economic environments. In summary, a heterogeneous, low-quality evidence base suggests an inconsistent moderating effect of low self-control on the effectiveness of interventions to change consumption behaviours

Personality correlates of susceptibility to peer influence in adolescence

Adolescents show a heightened susceptibility to peer influence compared to adults. Individual differences in this susceptibility exist, yet there has been little effort to link these with broader personality processes. Reward sensitivity and impulsive behaviour are also heightened in adolescence and could affect the tendency to be influenced by peers. This study examined associations between self-reported resistance to peer influence, facets of reward sensitivity and impulsivity, and subjective social status in a sample of 269 British sixth form students (mean age 16.79). Multiple regression analyses showed that negative and positive urgency were significantly negatively associated with resistance to peer influence. The relationship between negative urgency and resistance was moderated by subjective social status, such that individuals reporting low status showed a stronger negative relationship. Results suggest that a susceptibility to peer influence is linked with a tendency to act impulsively when in heightened emotional states. Adolescents high in negative urgency who feel lower in their social hierarchy may be particularly vulnerable

Viewing alcohol warning advertising reduces urges to drink in young adults: an online experiment

This is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/ 10.1186/s12889-016-3192-

Communicating the effectiveness and ineffectiveness of government policies and their impact on public support: a systematic review with meta-analysis.

Low public support for government interventions in health, environment and other policy domains can be a barrier to implementation. Communicating evidence of policy effectiveness has been used to influence attitudes towards policies, with mixed results. This review provides the first systematic synthesis of such studies. Eligible studies were randomized controlled experiments that included an intervention group that provided evidence of a policy's effectiveness or ineffectiveness at achieving a salient outcome, and measured policy support. From 6498 abstracts examined, there were 45 effect sizes from 36 eligible studies. In total, 35 (N = 30 858) communicated evidence of effectiveness, and 10 (N = 5078) communicated evidence of ineffectiveness. Random effects meta-analysis revealed that communicating evidence of a policy's effectiveness increased support for the policy (SMD = 0.11, 95% CI [0.07, 0.15], p < 0.0001), equivalent to support increasing from 50% to 54% (95% CI [53%, 56%]). Communicating evidence of ineffectiveness decreased policy support (SMD = -0.14, 95% CI [-0.22, -0.06], p < 0.001), equivalent to support decreasing from 50% to 44% (95% CI [41%, 47%]). These findings suggest that public support for policies in a range of domains is sensitive to evidence of their effectiveness, as well as their ineffectiveness

Impulsivity related personality traits and cigarette smoking in adults: A meta-analysis using the UPPS-P model of impulsivity and reward sensitivity

Background Although there is considerable evidence of an association between impulsivity and cigarette smoking, the magnitude of this association varies across studies. Impulsivity comprises several discrete traits that may influence cigarette use in different ways. The present meta-analysis aims to examine the direction and magnitude of relationships between specific impulsivity-related traits, namely lack of premeditation, lack of perseverance, sensation seeking, negative urgency, positive urgency and reward sensitivity and both smoking status and severity of nicotine dependence in adults across studies and to delineate differences in effects across these relationships. Methods Ninety-seven studies were meta-analysed using random-effects models to examine the relationship between impulsivity-related traits and smoking status and severity of nicotine dependence. A number of demographic and methodological variables were also assessed as potential moderators. Results Smoking status and severity of nicotine dependence were significantly associated with all impulsivity-related traits except reward sensitivity. Lack of premeditation and positive urgency showed the largest associations with smoking status (r = 0.20, r = 0.24 respectively), while positive urgency showed the largest association with severity of nicotine dependence (r = 0.23). Study design moderated associations between lack of premeditation and lack of perseverance and smoking status, with larger effects found in cross-sectional compared to prospective studies. Conclusions Finding suggest that impulsivity is associated with an increased likelihood of being a smoker and greater nicotine dependence. Specific impulsivity-related traits differentially relate to smoking status and severity of nicotine dependence. Understanding the complexity of impulsivity-related traits in relation to smoking can help to identify potential smokers and could inform cessation treatment

原著

For the purpose of investigating into the influence which is to be exercised by anaerobic bacteria lodged in the intestines of animals on their hosts, experiments were performed on the influence of Cl. welchii in germ-free chicks. Chicks of white leghorn were hatched in a germ-free environment, in chambers made germ-free by sterilization with steam under normal and high pressures. Germless chicks thus obtained were fed on an autoclaved diet, water and vitamins ; since the fifteenth day after being hatched, certain amount of the organisms of Cl. welchii mixed with autoclaved diet had been given to earth germless chicks. During this period, studies were made on the growth, increase in weight and germicidal power of the sera obtained from them. The results are summarized as follows : (1) An environment better suited for breeding germless chicks was provided by a tank designed to be made germ-free by sterilization with steam under high pressure than by one using normal pressure, with the result that the growth of chicks in the former was better than in the latter. (2) Oral administration of Cl. welchii to germless chicks caused diarrhea to take place and also an increase in weight to stop or a decrease in weight to occur. They, however, began to put on weight again in 5 or 7 days. But examinations carried out after a certain period showed that the increase of their weight was lower by about 50 per cent than the increase of weight of the chicks to which Cl. welchii had not been given (controls). (3) Germicidal power of the sera obtained from germless chicks was very low, while that of the sera obtained from the chicks to which Cl. welchii had been given was markedly high. (4) The results of the present experiments indicate that Cl. welchii, when given orally to germless chicks, may exert harmful influence on the growth of their hosts.The fact, however, that the germicidal power of chicks to which Cl. welchii had been given was higher than that of germless chicks suggests that the presence of this kind of bacteria in the intestines of animals may make the hosts more resistant to infection with other pathogenic organisms than otherwise