Assessment of quality control system by sigma metrics and quality goal index ratio: A roadmap towards preparation for NABL

Table 5 Sigma metrics of various parameters

Sigma metrics	Level 2	Level 3
< 3	Glucose, urea, total cholesterol, AST, ALT	Total cholesterol, AST, ALT
3-6	Creatinine, total bilirubin, total protein, calcium, phosphorus, triglyceride	Glucose, urea, total protein, calcium, triglyceride
> 6	Albumin, uric acid, HDL-cholesterol, ALP	Creatinine, total bilirubin, albumin, uric acid, HDL-cholesterol, ALP, amylase

HDL: High-density lipoprotein; AST: Aspartate transaminase; ALT: Alanine transaminase; ALP: Alkaline phosphatase.