Date	Event	Description
25 August 2021	New search has been performed	Second update, new search, 11 new trials included (Adisa 2011; Domes 2011; Grober 2013; Karegoudar 2012; Kattipattanapong 2013; Ko 1992; Kowalski 2016; Lu 2002; Sun 2014; Suvera 2013; Taylor 2005). Two trials that were awaiting classification have now been excluded (Fraser 1978; Menéndez 2004), and one additional trial is awaiting classification (Pascual 1994). Two findings within this update have changed from the previously updated version of this review. Previously, there was little difference between not removing hair and removing hair with a razor. Now, moderate‐certainty evidence shows that surgical site infections (SSIs) are probably lower when hair is not removed, although a sensitivity analysis found confidence intervals which narrowly included the possibilities of no effect or harm. Previously, there appeared to be no difference in SSIs between whether hair was removed by a razor or by cream. Moderate‐certainty evidence now shows that hair removal with cream probably results in fewer SSIs than hair removal with a razor. Two new findings show that more skin injury is probably sustained when hair is removed with razors compared with clippers (moderate‐certainty evidence) or with depilatory cream (low‐certainty evidence). A new subgroup has been created for the removal of hair from the male genital area. A narrative summary reports that clippers may cause more skin damage to male genitalia than razors (low‐certainty evidence), and that it is unclear whether there is a difference in SSIs between using razors or clippers on male genitalia (very low‐certainty evidence).
25 August 2021	New citation required and conclusions have changed	Updated. Conclusions changed.