Table 4.

Summary of guideline evolution at each development step

Key content	Step 1: rapid review (first draft)	Step 2: key informant interview (second draft)	Step 3: multi-stakeholder consultation (final draft)
Guideline principle	Save the most lives Save the most life-years Benefit to others	Save the most lives Save the most life-years Benefit to others	Utilitarianism: saving the most lives
Prioritization criteria	Apply three-order criteria: Clinical prognosis, e.g. SOFA, CFS; cognitive impairment assessment Number of life-years saved Social usefulness Allocation decisions are based on relative scores No cut-off score is applied	Apply three-order criteria: Clinical prognosis using one or more of the following tools: Charlson Comorbidity Index, SOFA, frailty assessment such as CFS, cognitive impairment assessment Number of life-years saved Social usefulness Allocation decisions are based on relative scores No cut-off score is applied	Assess patients based on clinical prognosis using at least two of the following tools: Charlson Comorbidity Index, SOFA, frailty assessment such as CFS, cognitive impairment assessment Allocation decisions are based on relative scores No cut-off score is applied Each health facility must apply the same sequence of tools consistently across all cases
Application	Applicable to all patients requiring critical care resources Prior to ICU admission Reassessment every 48 hours during ICU stay	Applicable to all patients requiring critical care resources Prior to ICU admission Reassessment every 48 hours during ICU stay	Applicable to all patients requiring critical care resources Prior to ICU admission Reassessment as appropriate during ICU stay
Decision-making	Triage committee of three healthcare professionals advises an attending physician on allocation	Attending physician is a decision-maker Triage committee of three healthcare professionals advises an attending physician on allocation	Attending physician is a decision-maker Patient review committee of five health and non-health experts advises an attending physician on allocation decision and communication with patient and families
Review process	Document assessment result and allocation decisions in a registry Registry information can be reviewed by a staff/team in the hospital who are not involved in the first decision or external expert(s) Appeal mechanism was proposed to be considered	Document assessment results and allocation decisions in a registry Registry information can be reviewed by a staff/team in the hospital who are not involved in the first decision or external expert(s) Appeal mechanism was proposed to be considered	Document assessment results and allocation decisions in a registry Registry information can be reviewed by a staff/team in the hospital who are not involved in the first decision or external expert(s)
Implementation	When only 10–20% of critical care resources remain available	When only 10–20% of critical care resources remain available	National public health emergency AND All efforts have been made to mobilize resources and demand still exceeds supply
Enforcement	The guideline is to be endorsed by the Medical Council of Thailand	The guideline is to be endorsed by the Medical Council of Thailand	The guideline is to be endorsed by the Medical Council of Thailand. Current status of endorsement is unclear due to the pandemic’s changing situation

SOFA Sequential Organ Failure Assessment, CFS Clinical Frailty Scale