Physician spouses making a difference.

OBJECTIVE: To test a survey method for estimating the coverage of selective feeding programmes in humanitarian emergencies. METHODS: The trial survey used a stratified design with strata that were defined using the centric systematic area sample method. Thirty 100 km2 quadrats were sampled. The communities located closest to the centre of each quadrat were sampled using a case-finding approach. FINDINGS: The method proved simple and rapid to implement and allowed overall and per-quadrat coverage to be estimated. Overall coverage was 20.0% (95% confidence intervals, 13.8-26.3%). Per-quadrat coverage ranged from zero (in nine quadrats) to 50% (in one quadrat). Coverage was highest in the quadrats closest to therapeutic feeding centres and in quadrats containing major roads leading to the towns in which therapeutic feeding centres were located. CONCLUSION: The method should be used, in preference to WHO Expanded Programme on Immunization (EPI)-derived survey methods, for estimating the coverage of selective feeding programmes. Its use should also be considered when evaluating the coverage of other selective entry programmes or when coverage is likely to be spatially inhomogeneous.

Altruism↗

PubMed2005

Effects of information and group structure on evolution of altruism: analysis of two-score model by covariance and contextual analyses.

An altruistic individual has to gamble on cooperation to a stranger because it does not know whether the stranger is trustworthy before direct interaction. Nowak and Sigmund (Nature 393 (1998a) 573; J. Theor. Biol. 194 (1998b) 561) presented a new theoretical framework of indirect reciprocal altruism by image scoring game where all individuals are informed about a partner's behavior from its image score without direct interaction. Interestingly, in a simplified version of the image scoring game, the evolutionarily stability condition for altruism became a similar form of Hamilton's rule, i.e. inequality that the probability of getting correct information is more than the ratio of cost to benefit. Since the Hamilton's rule was derived by evolutionarily stable analysis, the evolutionary meaning of the probability of getting correct information has not been clearly examined in terms of kin and group selection. In this study, we applied covariance analysis to the two-score model for deriving the Hamilton's rule. We confirmed that the probability of getting correct information was proportional to the bias of altruistic interactions caused by using information about a partner's image score. The Hamilton's rule was dependent on the number of game bouts even though the information reduced the risk of cooperation to selfish one at the first encounter. In addition, we incorporated group structure to the two-score model to examine whether the probability of getting correct information affect selection for altruism by group selection. We calculated a Hamilton's rule of group selection by contextual analysis. Group selection is very effective when either the probability of getting correct information or that of future interaction, or both are low. The two Hamilton's rules derived by covariance and contextual analyses demonstrated the effects of information and group structure on the evolution of altruism. We inferred that information about a partner's behavior and group structure can produce flexible pathways for the evolution of altruism.

Altruism↗