This application is called the IDIOM App; Iron Deficiency as an Indicator of Malignancy. It has been developed as part of a match−fund PhD project between Bournemouth University and Poole Hospital NHS Foundation Trust in the period of Sep 2017−March 2021. The PhD project examined the association between iron deficiency anaemia (IDA) and gastro−intestinal (GI) cancer by analysing secondary anonymised datasets. The app consists of two major components; an internal algorithm to predict the GI cancer risk in IDA patients. And a web−based interface to allow selecting input data (sex, age, haemoglobin concentration (Hb), and mean red cell volume (MCV)); presenting the results (based on inputs data); displaying the app terms of use, privacy and data protection notice, and app information; enabling the communication with the app research and maintenance teams; and printing (or saving) the results when needed.
Using merely four predictors (input data); sex, age, haemoglobin concentration (Hb), and mean red cell volume (MCV), the app calculates the risk of any type of GI cancer for a specific iron−deficient patient to inform the healthcare professional' decisions on the patient' future clinical management including GI cancer investigations. The results of the calculations are displayed in a table that contains the selected predictors' values of sex, age, Hb, MCV for the patient. And the risk estimate with its 95% confidence interval and the risk group of the patient based on the risk estimate. This table is followed by an explanation of the risk estimate, confidence interval of the risk, and the risk groups. The risk estimate represents a probability (in a percentage format) that an individual confirmed ID patient with the particular set of predictors entered will prove on investigation to has a cancer somewhere in his/her GI tract. Though this probability risk provides a realistic estimate of any potential GI cancer, it implies no certainty about the presence of GI cancer. The confidence interval of the predicted risk represents a range of values that predicts where the risk will fall for a population of confirmed ID patients who share the selected values of sex, age, Hb, and MCV with 95% confidence interval. Risk groups are classifications that describe IDA patients who fall within certain ranges of risk estimates values of positive GI malignancy. The stratification of risk groups is based on positive predictive values (PPV) quartiles, with the lowest quartile divided in two (table 1).
Table 1 risk groups along with their risk estimates and PPV
| Risk Group | Risk estimate | Risk group accounting for % of the cohort | PPV |
|---|---|---|---|
| very-low | <1.5% | 10% | Q1 (100% *NPV) |
| low | 1.5-2.8% | 14% | Q1 |
| moderate | 2.8-5.5% | 25% | Q2 |
| high | 5.5-11% | 26% | Q3 |
| very-high | ≥11% | 25% | Q4 |
*NPV: negative predictive value
The very−low risk group is corresponding to 100% negative predictive value. This means that none of the individuals with a risk predicted by the model of less than 1.5% are proved to have GI cancer on investigation. The very high−risk group is corresponding to more than 18.5% PPV value (values are in the upper quartile of PPV) and accounting to about 25% of the whole cohort. If the predicted risk of GI cancer is very low, the risk figure will be displayed in dark green font colour and the risk and groups' cells in light green background colour. If the predicted risk of GI cancer is low, the risk figure will be displayed in dark green font colour and the risk and groups' cells in white background colour. If the predicted risk of GI cancer is moderate, the risk figure will be displayed in black font colour and the risk and groups' cells in white background colour. If the predicted risk of GI cancer is high, the risk figure will be displayed in red font colour and the risk and groups' cells in white background colour. If the predicted risk of GI cancer is very high, the risk figure will be displayed in red font colour and the risk and groups' cells in amber background colour.
The intended patients' population for this app are the confirmed iron−deficient patients (adults only). Confirmed iron deficiency is defined by standard laboratory criteria; transferrin saturation <15% and / or serum ferritin concentration less than the lower limit of the reference interval for the laboratory.
The intended targeted end users for the software are healthcare professionals only such as gastroenterologists, and specialist nurses. And the environment in which this app will be used is a clinical setting such as IDA clinics, gastroenterology departments in hospitals.
Stand−alone, Clinical decision−support (CDS) software, none−sterile, none−measuring, none−reusable surgical instrument, active class I medical device.
App Version 1.0, Date of release 1st Dec 2020, BU Innovations Limited (BUI), 2nd floor 2nd Floor Melbury House, 1-3 Oxford Road, Bournemouth, Dorset, UK.
BU Innovations Limited (BUI), 2nd floor 2nd Floor Melbury House, 1-3 Oxford Road, Bournemouth, BH8 8ES, Dorset, UK. TEL: +44 (0)1202 961200
This app has been lawfully placed on the market pursuant to MDD ( Medical Devices Directive) prior to 26 May 2021, and it may continue to be made available up to 5 years from the certificate' issue date or 4 years from the MDR date of application (May 2021), whichever comes first. Maintenance is expected to be run routinely during the expected lifetime of this app, and it will involve bug−fixing and routine updates.