Root Cause Analysis in Healthcare — How to Investigate Quality Failures

Root Cause Analysis (RCA) is the process of identifying the underlying reasons for a quality failure — not just the immediate cause, but the deeper systemic factors that allowed the failure to occur.

Without proper RCA, corrective actions address symptoms rather than causes, and the same problems recur. Effective RCA is a critical skill for any quality professional in a NABL or NABH-accredited facility.

The 5-Why Technique

The simplest RCA technique. For each problem, ask “Why?” five times, each time going deeper than the previous answer.

Example: Patient sample mislabelled

• Why? → Phlebotomist labelled the tube at the workstation, not at the bedside
• Why? → The SOP says to label at the bedside, but the workstation is more convenient
• Why? → The SOP was not enforced, and supervisors did not correct the shortcut
• Why? → Supervision is inadequate during peak collection hours
• Why? → No formal supervisory rounding protocol during peak hours

Root cause: Inadequate supervision during peak collection hours, allowing SOP deviation to become routine practice.

Fishbone (Ishikawa) Diagram

For more complex failures, the fishbone diagram maps causes across 6 categories (the 6 Ms):

• Man: Human factors (training, competency, fatigue)
• Machine: Equipment factors (malfunction, calibration)
• Method: Process factors (SOP inadequacy, unclear steps)
• Material: Reagent or supply factors
• Measurement: Monitoring and QC factors
• Environment: Physical environment factors (space, temperature, distraction)