What factors are contributing to the increased error rate in Verily's Study Watch ECG readings observed in the last quarter?

Introduction

The increased error rate in Verily's Study Watch ECG readings observed in the last quarter is a critical issue that demands immediate attention. This analysis will systematically identify, validate, and address the root cause while considering both short-term fixes and long-term implications for the product.

I'll approach this problem by first clarifying key details, ruling out external factors, and then diving deep into the product's user journey and metrics. From there, I'll generate data-driven hypotheses, conduct root cause analysis, and propose validation methods and solutions.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking there might be a seasonal component. Has this increase in error rate been observed in previous years during the same quarter?

Why it matters: Seasonal patterns could indicate external factors rather than product issues. Expected answer: No seasonal pattern observed in previous years. Impact on approach: If seasonal, we'd focus on environmental factors; if not, we'd prioritize internal product and technical investigations.

• Considering user segments, I'm curious about the distribution of errors. Are we seeing this increased error rate across all user demographics, or is it concentrated in specific groups?

Why it matters: Helps identify if the issue is universal or related to specific user characteristics. Expected answer: The error rate increase is seen across all demographics. Impact on approach: If universal, we'd focus on system-wide issues; if specific, we'd investigate user-related factors.

• Thinking about recent changes, have there been any software updates or hardware modifications to the Study Watch in the last quarter?

Why it matters: Recent changes could be directly linked to the increased error rate. Expected answer: A minor software update was rolled out at the beginning of the quarter. Impact on approach: If changes occurred, we'd prioritize investigating those specific modifications.

• Regarding data integrity, has there been any change in how we're measuring or defining ECG reading errors?

Why it matters: Ensures we're comparing apples to apples and not seeing a false increase due to measurement changes. Expected answer: No changes in error measurement or definition. Impact on approach: If changed, we'd need to recalibrate our analysis based on the new measurement criteria.