Total Code Quality Index (TCQI)

The Total Code Quality Index (TCQI) is a composite metric in Oobeya that quantifies code quality by analyzing SonarQube issue data through multiple lenses: severity, category impact (security, reliability, maintainability), remediation effort, and codebase volume. It provides engineering leaders with a clear, standardized, and customizable way to monitor and improve software quality.

---

What TCQI Measures

The TCQI goes beyond raw issue counts. It evaluates:

• How risky issues are, based on severity and fix effort.

• What impact they have across key quality dimensions.

• How clean the codebase is by factoring in total code volume.

• How the project compares to an ideal maximum through normalization.

This results in a set of actionable, easy-to-compare indices:

• Total Code Quality Index (TCQI)

• Security Index

• Reliability Index

• Maintainability Index

---

Core Concepts

TCQI is built on three core inputs from SonarQube:

Dimension	Description
Severity	Indicates how critical an issue is (Blocker, High, Medium, etc.).
Quality Categories	Reflects the issue’s domain: Security, Reliability, Maintainability. An issue may belong to more than one category.
Remediation Effort	The estimated time required to fix the issue (e.g., 10 minutes, 8 hours, etc.).

These inputs are transformed into scores using configurable coefficients defined by your organization.

---

Configurable Coefficients

All coefficients can be customized in Admin Settings > Code Quality > Code Quality Index.

🔸 Severity Coefficients

Severity	Coefficient
High	0.6
Medium	0.3
Low	0.1

🔸 Quality Category Coefficients

Category	Coefficient
Security	0.55
Reliability	0.35
Maintainability	0.1

---

Step-by-Step Calculation

1. Calculate Issue Risk Scores

Each issue is scored independently per quality category it belongs to:

Issue_Risk_Score = Severity_Coefficient × Category_Coefficient × Remediation_Effort

Because issues may belong to multiple categories, the same issue may contribute to multiple risk scores (e.g., both Security and Reliability).

---

2. Calculate Project-Level Category Risk Scores

For each category:

Project Category Risk Score = Sum(Issue Risk for that category)

Project Security Risk Score = Sum(Security_Issue_Risk_Score)
Project Reliability Risk Score = Sum(Reliability_Issue_Risk_Score)
Project Maintainability Risk Score = Sum(Maintainability_Issue_Risk_Score)

---

3. Final Total Code Quality Index (TCQI) Formula

Total_Risk_Score = Sum(Issue_Risk_Score)

TCQI = 5 × (1− (Total_Risk_Score / (Lines_of_Code + Total_Risk_Score)​)

---

Why Use TCQI?

• Standardized and Scalable: Works across small and large codebases alike.

• Actionable: Highlights critical areas in security, reliability, or maintainability.

• Customizable: Adapt coefficients to align with your company’s engineering standards.

• Measurable Over Time: Track quality regressions or improvements release by release.

---

Where to Configure

To tailor the TCQI model to your organization:

Go to: Admin Settings > Code Quality > Code Quality Index

There, you can:

• Define severity weights

• Set quality category priorities

---

Summary

Oobeya’s Total Code Quality Index provides a balanced, flexible, and insightful view of your engineering organization’s code health. It connects static code analysis to strategic engineering decisions—helping you drive long-term quality improvements.