Short-term biological variation of clinical chemical values in Dumeril's monitors (Varanus dumerili).

Plasma biochemical values are routinely used in the medical management of ill reptiles, and for monitoring the health of clinically normal animals. Laboratory tests, including clinical biochemical values, are subject to biological and analytical variation, the magnitude of which determines the utility of population-based reference ranges for the detection of abnormal results in the individual animal. Nested analysis of variance of repeated measurements allows the variance to be broken into within-individual, between-individual, and analytical variation. When the within-individual variation is large and the interindividual variation is low, a sample may be accurately classified as normal or abnormal based on a population-based reference interval. However, if the intraindividual variation is low and the interindividual variation high, population-based reference intervals are of limited value as the ranges for an individual encompass only a part of the conventional reference interval. Between-lizard, within-lizard, and analytical components of variance were assessed by nested analysis of variance for 16 commonly measured plasma biochemical parameters in eight healthy adult Dumeril's monitors (Varanus dumerili). Albumin, cholesterol, phosphate, calcium, sodium, and total protein demonstrated levels of individuality suggesting that comparison of a single measurement to a conventional population-based reference range may be too insensitive to detect small but significant alterations in the value for that animal. Only for potassium and AST did the index of individuality suggest that the use of reference values may be warranted. Uric acid, globulin, glucose, and amylase fell in a gray zone, where population-based ranges should be used with caution. The critical difference indicates the difference between two consecutive analytical results that may be safely ascribed to natural variation. In the present study critical difference varied from 7 and 11%, respectively, for sodium and chloride to 75 and 125% for uric acid and AST.

Using community ties to facilitate school-based prevention research.

One of the greatest obstacles to conducting school-based HIV/STD/pregnancy prevention research with adolescents is the reluctance of administrators or site-based decision-making councils to commit their teachers and students to participation in a project designed and managed by an outside group of researchers. A major concern is that researchers may not understand or agree with community sensitivities about such personal topics. By first establishing a collaborative relationship with health district educators currently working in Appalachian schools and residing in those communities, one finds a distinct advantage in terms of gaining admittance to area schools. The presence of local health educators at formative meetings also alloys many concerns of community members, as they view these local participants as monitors of outsider research efforts, thereby protecting the community culture from undue outside influence. During the course of the current study, health educators found they also learned more about their communities and about HIV prevention.