Trata-se de pesquisa qualitativa que tem por objetivo analisar as relações de poder estabelecidas no trabalho da Estratégia Saúde da Família. Foram realizadas entrevistas semiestruturadas com dezenove profissionais integrantes de três equipes e utilizados registros efetuados a partir de observação participante. Os dados foram analisados segundo Bardin e categorizados em duas unidades analíticas. O estudo demonstrou que alguns paradigmas são difíceis de modificar, especialmente quando são vistos de forma natural pelos envolvidos. No entanto, avanços foram verificados a partir do posicionamento daqueles muitas vezes vistos como inferiores nas relações de poder desse serviço.

Background: The laboratory tests most used by blood banks to diagnose anemia are the hemoglobin (Hb) and microhematocrit (Hct) tests, measured from capillary samples. Objective: To analyze the two capillary screening methods for pre-donation anemia by comparing their agreement in diagnosing anemia. Method: A cross-sectional study in a population of 15,521 blood donation candidates for whom information was available on Hb and Hct, performed from capillary blood samples. Hb was determined using the HemoCue^® test and Hct by the centrifugation method. The Kappa coefficient was calculated to assess the agreement between the methods. Pearson’s correlation tests and gender-adjusted linear regression were used to assess the change in the response variable (Hb) as a function of the explanatory variable (Hct). Results: The majority of the study population were men (70.4%), aged between 18 and 44 years (72.1%), who declared themselves white or mixed skin color (85.6%), and had undergone at least 11 years of complete education (72.4%). The Kappa coefficient found was 92.7 and 99.2 for women and men, respectively. Pearson’s correlation showed a correlation coefficient of 0.98 and the linear regression graph showed an adequate relationship between the tests with R² = 0.97. Conclusions: Comparing the Hb and Hct capillary tests, it was found that Hct can be safely used to screen for anemia in pre-blood donation.