How do you conduct a comprehensive process capability study for a critical dimension?

Comprehensive capability study involves: Measurement system analysis (Gage R&R - target <10% of tolerance), Data collection strategy (minimum 50 parts over time representing normal variation, subgroups for within/between variation), Normality assessment (histogram, normal probability plot, Anderson-Darling test), Control chart analysis (verify statistical control before capability calculation), Capability indices calculation (Cp, Cpk for short-term; Pp, Ppk for long-term), Non-normal data handling (transform or use non-normal methods if needed), Confidence intervals for indices, and Process improvement if Cpk <1.33. For Six Sigma target Cpk >1.67. Report includes histogram with spec limits, control charts, capability summary, and improvement recommendations. Common in automotive (PPAP), aerospace (FAI), and medical device (process validation) industries.