Несколько сильных критических замечаний по близнецовому методу и усыновлению: R. Rose, “Genes and Human Behavior,” Ann Rev Psych 467 (1995): 625; J. Joseph, “Twin Studies in Psychiatry and Psychology: Science or Pseudoscience?” Psychiatric Quarterly 73 (2002): 71; K. Richardson and S. Norgate, “The Equal Environments Assumption of Classical Twin Studies May Not Hold,” Brit J Educational Psych 75 (2005): 339; R. Fosse et al., “A Critical Assessment of the Equal-Environment Assumption of the Twin Method for Schizophrenia,” Front Psychiatry 6 (2015): 62; A. V. Horwitz et al., “Rethinking Twins and Environments: Possible Social Sources for Assumed Genetic Influences in Twin Research,” J Health and Soc Behav 44 (2003): 111.