NEW DELHI: Long and crushing working hours have become a serious challenge for resident doctors, causing them psychological distress and mental health problems. Flagging the issue in an affidavit before Supreme Court, National Medical Commission (NMC) has stressed that reasonable working hours and time for rest are a must for their wellbeing and proper functioning, as well as proper patient care. It, however, expressed its inability to ensure the same, saying the matter falls within the domain of central and state health authorities.