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Introduction Iron Deficiency Anaemia (IDA) represents 10% of referrals to gastrointestinal (GI) services. In November 2021, the Scottish government published a symptom-based pathway to allow ‘decoupling’ of bidirectional GI investigations. Stool FIT testing is superior to symptoms for assessing risk of colorectal cancer. A recent single-unit small study in NHS Lothian evaluated FIT testing to safely stratify referrals and prioritise IDA investigations. Our current study aims to validate this in a larger multi-centre cohort.Methods A retrospective study was completed on patients referred with IDA to two tertiary hospitals in NHS Lothian from June to September 2024. All IDA referrals were triaged by a single luminal GI consultant who used the FIT-directed pathway. Data was then collected from patients’ electronic patient record (EPR) including demographics, clinical frailty score (CFS), FIT results and ultimate diagnostic investigations to assess whether FIT effectively identified those with high-risk pathology.Results 499 patients were referred to GI services for IDA with 455 having confirmed IDA. Of these, 348 completed FIT testing, with remaining patients either incompliant with the test or reviewed in clinic due to clinical complexity. 299 patients proceeded to upper GI endoscopy, 132 to colonoscopy and 139 undertook a CT colon to investigate their IDA.In patients with a positive FIT test (n=118), 12 (10%) were diagnosed with colorectal and 2 (1%) diagnosed with gastric cancer. 6 patients had high risk polyps and 8 were diagnosed with conditions requiring monitoring, such as Barrett’s Oesophagus. 88 (74%) had no significant pathology when investigated. In the double-negative FIT cohort (n=230), there was 2 upper GI malignancies but no colorectal cancers diagnosed (figure 1). 31 (13%) patients had conditions that required monitoring but 195 (85%) had no significant pathology.In this study, the sensitivity and specificity of FIT for colorectal cancer was 1 and 0.69 respectively. For all cancers, sensitivity was 0.84 and specificity was 0.69. 67 patients were identified as frail (CFS ≥ 5). 13 were not investigated further due to frailty. Gastrointestinal malignancy was identified in 2 frail patients. There was no statistical difference in cases of malignancy in frail patients versus non-frail patients (p=0.2).Conclusions A FIT testing directed IDA pathway safely de-couples bidirectional endoscopy effectively and can stratify patients based on their risk of colorectal cancer and other significant pathologies. Double-negative FIT individuals may not need colonic investigations, but this finding would need further validation in larger cohorts. Clinical frailty should be assessed for IDA and investigations tailored based on their fitness for tests. These findings support our local IDA protocol and aligns with national BSG guidelines for investigating IDA using FIT.