The reduced mortality observed in the registry data could not be confirmed in our meta\analyses. Data collection and analysis Three authors extracted data. We derived risk ratios (RR) for dichotomous data and imply differences (MD) for continuous data with 95% confidence intervals (CI). Methodological risk of bias was assessed using the Cochrane risk of bias tool and trial sequential analyses were undertaken to assess the risk of random errors (play of chance). Main results Our review included six RCTs (representing a total of 278 adult lung transplant recipients) that assessed the use of T\cell antibody induction. Evaluation of the included studies found all to be at high risk of bias. We conducted comparisons of polyclonal or monoclonal T\cell antibody induction versus no induction (3 studies, 140 participants); polyclonal T\cell antibody versus no induction (3 studies, 125 participants); interleukin\2 receptor antagonists (IL\2RA) versus no induction (1 study, 25 participants); polyclonal T\cell antibody versus muromonab\CD3 (1 study, 64 participants); and polyclonal T\cell antibody versus IL\2RA (3 studies, 100 participants). Overall we found no significant differences among interventions in terms of mortality, acute rejection, adverse effects, contamination, pneumonia, cytomegalovirus contamination, bronchiolitis obliterans syndrome, post\transplantation lymphoproliferative disease, or malignancy. We found a significant end result difference in one study that compared antithymocyte NPPB globulin versus muromonab\CD3 relating to adverse events (25/34 (74%) versus 12/30 (40%); RR 1.84, 95% CI 1.13 to 2.98). This suggested that antithymocyte globulin increased occurrence of adverse events. However, trial sequential analysis found that the required information size had not been reached, and the cumulative Z\curve did not cross the trial sequential alpha\spending monitoring boundaries. None of the studies reported quality of life or kidney injury. Trial sequential analyses indicated that none of the meta\analyses achieved required information sizes and the cumulative Z\curves did not cross the trial sequential alpha\spending monitoring NPPB boundaries, nor reached the area of futility. Authors’ conclusions No obvious benefits or harms associated with the use of T\cell antibody induction compared with no induction, or when different types of T\cell antibodies were compared were identified in this review. Few studies were identified that investigated use of antibodies against T\cells for induction after lung transplantation, and numbers of participants and outcomes were also limited. Assessment of the included studies found that all were at high risk of methodological bias. Further RCTs are needed to perform strong assessment of the benefits and harms of T\cell antibody induction for lung transplant recipients. Future studies should be designed and conducted according to methodologies to reduce risks of systematic error (bias) and random error (play of NPPB chance). (Higgins 2011) and conducted trial sequential analysis (Wetterslev 2008; TSA 2011). The quality and quantity of available evidence limited our findings and interpretations. Very limited numbers of participants were included in the studies, and hence, risks of random errors potentially explain occasional positive findings in individual studies. Additionally, study participants may not be representative of the general patient populace. Follow\up BMP2B in five studies was between six months NPPB and two years; and eight years in one study. We therefore were unable to elicit evidence relating to longer\term (greater than two years) effects NPPB of T\cell antibody induction on end result measures. Long\term effects in terms of mortality, bronchiolitis obliterans syndrome, contamination, and malignancy would be particularly useful. We explored the presence of statistical heterogeneity using the Chi2 test and measured heterogeneity using the I2 test (Higgins 2003). The Chi2 test is usually low powered in meta\analyses where studies are small or few in number, as in this review. This means that while a statistically significant result may indicate a problem with heterogeneity, a non\significant result must not be taken as evidence of homogeneity..