Does Pinning a Mobile Checkout CTA Improve Conversion?
Hypothesis
On a mobile multi-step checkout/enrollment flow with a long verification page, users may struggle to find the primary action when they reach the bottom. Making the primary CTA persistently visible should reduce friction and improve progression to the confirmation step.
Evidence: E1 Reported only
An outcome is reported, but there is not enough disclosed information to check whether the result is reliable.
Why this rating
Use for inspiration or follow-up, not as proof.
Integrity: Caution. Analysis: Unknown.
Missing for a higher tier: Control description, Variant description, Positive sample size, Positive duration, Valid arm counts, Expected allocation, and more.
Caution: Stored caution integrity status, Analysis method not independently specified.
Read the evidence-rating methodologyKey Learning
Sticky mobile CTAs can compress time-on-page meaningfully (~15% faster) without sacrificing engagement signals — users converted at a directionally higher rate AND moved through the page faster, suggesting reduced hesitation rather than rushed clicks. The result was shipped via 90/10 holdout monitoring rather than traditional 50/50 A/B inference — the high baseline (~85%) and limited mobile traffic made full A/B underpowered, so the team chose a holdout-validated rollout as the deliberate methodology. Bayesian P(variant > control) was ~0.90, supporting the directional ship call.
How to Apply This to Your Site
The reported outcome labels this treatment a winner. The record reports an improvement in the measured outcome. The test was run on a checkout page in the energy & utilities industry. Treat it as context for a new hypothesis, not as an expected lift for another site.
Before you test: use your own baseline, business MDE, traffic, and risk tolerance to set the sample and stopping rule. Declare whether the analysis is fixed-horizon, sequential, or Bayesian before launch, and log campaign, targeting, instrumentation, and concurrent-experiment changes while it runs.
What Was Tested
Mobile-only test on a verification step with a high baseline conversion rate (~85%) where the primary CTA was anchored at the bottom of a long page. The variant pinned the CTA to the bottom of the viewport on scroll.
Methodology
Build On These Learnings
Save your plans, results, context, and limitations so the next decision can use the strongest available evidence without treating every outcome as universal.