## Diagram: Patient Data Collection and Selection Flow ### Overview This image presents a flowchart detailing the process of collecting and selecting patient data for a study. It illustrates the initial number of patients, subsequent filtering steps based on data availability, and the final count of patients included and excluded from the study. The diagram uses rectangular nodes to represent stages or groups of patients and directed arrows to show the flow or progression. ### Components/Axes The diagram consists of six rectangular nodes, each containing descriptive text and a patient count (N), connected by five directed arrows indicating the flow of the process. There are no traditional axes, legends, or specific color coding beyond black text on a white background within black-bordered rectangles. ### Detailed Analysis The flow proceeds from top to bottom, with a branching point in the middle. 1. **Top Node (Center-Top):** * Text: "Data collected from\nPatients\n(N=211)" * This node represents the initial pool of data collected from 211 patients. * An arrow points downwards from this node. 2. **Second Node (Center, below the Top Node):** * Text: "Data collected from the\nmedical records of patients\n(N=179)" * This node indicates a subset of 179 patients from whom data was collected specifically from medical records. This suggests 32 patients (211 - 179) were not included in this medical record data collection step or were excluded prior to it. * Two arrows originate from this node, branching downwards and outwards to the left and right. 3. **Third Node (Bottom-Left, below the Second Node):** * Text: "Patients with all the\nnecessary data\n(N=117)" * This node represents 117 patients who had all the required data. This group is a direct outcome of the "Data collected from medical records" step. * No arrows originate from this node, indicating it's an endpoint or a group not further processed in this specific flow. 4. **Fourth Node (Bottom-Right, below the Second Node):** * Text: "Patients with missing\nmedical record data\n(N=62)" * This node represents 62 patients who had missing data in their medical records. This group, along with the "Patients with all the necessary data" (N=117), sums up to the 179 patients from the previous step (117 + 62 = 179). * Two arrows originate from this node, branching downwards and outwards to the left and right. 5. **Fifth Node (Bottom-Most Left, below the Fourth Node):** * Text: "Patients excluded from\nthe study due to missing\ndata\n(N=11)" * This node represents 11 patients who were explicitly excluded from the study because of missing data. This group is a subset of the "Patients with missing medical record data" (N=62). * No arrows originate from this node. 6. **Sixth Node (Bottom-Most Right, below the Fourth Node):** * Text: "Patients included\nin the study\n(N=51)" * This node represents 51 patients who were ultimately included in the study. This group is also a subset of the "Patients with missing medical record data" (N=62), implying that despite some initial missing data, 51 patients were still deemed suitable for inclusion (perhaps after further review or imputation). The sum of this group and the excluded group (11 + 51 = 62) matches the "Patients with missing medical record data" count. * No arrows originate from this node. ### Key Observations * The diagram clearly illustrates a patient selection funnel, starting with a larger group and narrowing down to a final study population. * The numbers (N values) are consistent at each branching point, demonstrating a clear accounting of patients as they move through the selection process. * The primary reason for exclusion explicitly stated is "missing data." * The process distinguishes between patients with complete data and those with missing data, and then further processes the latter group. ### Interpretation This flowchart describes a common methodology in research studies, particularly in medical or clinical fields, for patient recruitment and data management. It demonstrates a systematic approach to handling patient data, starting from an initial collection and moving through stages of refinement and exclusion. The initial step of "Data collected from Patients (N=211)" suggests a broader initial contact or data source. The subsequent step, "Data collected from the medical records of patients (N=179)," indicates a specific focus on medical record data, leading to an initial reduction of 32 patients (211 - 179). This reduction could be due to patients not having medical records, or their records not being accessible, or other initial exclusion criteria not detailed here. The core of the selection process lies in the split of the 179 patients into those with "all the necessary data (N=117)" and those with "missing medical record data (N=62)." This highlights a critical decision point based on data completeness. Interestingly, the "Patients with missing medical record data (N=62)" group is further processed, resulting in "Patients excluded from the study due to missing data (N=11)" and "Patients included in the study (N=51)." This implies that not all patients with *some* missing data were automatically excluded. There might have been a secondary review, a threshold for acceptable missingness, or specific types of missing data that were deemed non-critical for the study's objectives, allowing 51 of these patients to be included. The final outcome shows two main groups of patients contributing to the study: the 117 patients who initially had all necessary data, and the 51 patients who, despite some missing data, were ultimately included. The total number of patients included in the study would be 117 + 51 = 168. The diagram effectively communicates the transparency and rigor of the patient selection process, accounting for every patient at each stage.