E-commerce Integrity module (30 checks)

Duplicate purchase detection

Duplicate purchase events are the most costly e-commerce tracking error — they inflate revenue and conversion rates. The module analyses the ratio of unique transaction IDs to total purchase events; below 1.0 (the same transaction ID appearing multiple times) is a critical finding.

Usual causes: the confirmation page firing on every reload, or both server-side and client-side tracking sending the same event without deduplication.

Missing item parameters

The GA4 e-commerce schema requires item_id, item_name, price, and quantity. Missing parameters create blank rows in product reports and break item-level analysis. The module checks parameter coverage across purchase, add_to_cart, and view_item.

Checkout funnel gap analysis

A healthy checkout funnel shrinks progressively from begin_checkout to add_payment_info to purchase. Anomalous ratios — more purchases than begin_checkout, or begin_checkout far exceeding add_to_cart — point to missing event instrumentation at one or more steps.

Currency consistency

If transactions are reported in multiple currencies without consistent currency codes, GA4 cannot aggregate revenue accurately. The module checks whether multiple currency codes appear in purchase events and whether the property's currency setting matches the dominant currency in the data. Mixed currencies without proper handling is flagged as a high-severity finding.

Refund tracking

GA4 supports refund tracking via the refund event. The module checks whether refund events are present and, if your property processes a non-trivial volume of transactions, flags the absence of refund tracking as a medium-severity issue. Without refunds, reported revenue in GA4 will be higher than actual net revenue.