Goldman et al. noted that "increased stringency in the 1993 InterQual ISD instrument probably led to its decreased sensitivity for continued-stay judgments as compared to the 1992 InterQual ISD Criteria." As they noted, the increased stringency came about because the 1993 InterQual criteria set was the only one to require frequent nursing monitoring, daily psychiatrist contact, and treatments requiring an inpatient setting. Although stringent, these are not unreasonable requirements for continued stay. The purpose of stringent criteria is to create a system for early warning that a patient may be ready for a lower level of care.