What is the recommended duration for an incrementality test to capture meaningful lift insights?

An incrementality test should run for at least 2 weeks to capture meaningful lift insights. This duration allows enough time to observe campaign performance and user behavior across both the test and control groups, accounting for weekly cycles and initial campaign ramp-up. Shorter durations might not provide statistically significant results, as they could be influenced by day-to-day fluctuations or insufficient data volume. Longer durations, such as 2 months, 90 days, or 6 months, are not strictly necessary for initial meaningful insights and can delay decision-making. While longer tests can provide more robust data, 2 weeks is generally considered the minimum viable period to detect a measurable impact.