“…Two surgical factors related to the parathyroid glands showed repeated significant associations with transient biochemical hypocalcaemia. These included an increasing number of parathyroid glands left in situ at the time of surgery (significant results in four of four studies 18,28,32,34 ), and evidence of parathyroid glands in the pathology specimen (8 significant results from 12 studies) 20,33,38,42,46–49 . However, other surgical factors related to the parathyroid glands do not demonstrate the same connection; a higher number of parathyroid glands identified during the procedure was more frequently not statistically significant (six of nine results were not significant 31,34,40,43,50,51 ) and equivocal results were seen when parathyroid glands are auto-transplanted (nine results significant 19,20,33,38,42,47–49,52 , eight non-significant 19,30,50,53–57 ).…”