Studies reporting data on core body temperature of infants with gestational age < 28 weeks were assessed for publication bias (Egger’s test, P = 0.200, Begg’s test, P = 0.029). The statistical testing revealed an apparent difference that suggested the presence of a potential publication bias, a language bias, and inflated estimates by a flawed methodological design in smaller studies,and/or a lack of publication of small trials with contradictory results.