Table 5.

Results of Cluster Analysis by Method.

Methodology	Solution	Description of Solution
Factor Analysis (PCA, EFA, and CFA)	Four-factor solution (SPSS and SAS)	1. Chest symptoms 2. Exertion-like symptoms 3. Pain: non-chest 4. Gastrointestinal
Hierarchical Agglomerative Analysis	Three-cluster solution (optCluster)	1. Heavy symptom burden (indigestion lightheadedness, nausea, fatigue, arm pain, upper back pain, sweating, shoulder pain) 2. Chest symptoms (chest pain, chest discomfort, chest pressure) 3. Classic symptoms (chest pain, lightheadedness, fatigue, shortness of breath, chest discomfort, chest pressure)
k-means Cluster Analysis	Six clusters (SPSS) Based on cluster centers	1. Gastrointestinal (sweating, fatigue, lightheadedness) 2. Low symptom burden (no symptoms with high probability of occurrence) 3. Heavy symptom burden (chest pressure, shoulder pain, sweating, palpitations, chest discomfort, upper back pain, shortness of breath, arm pain, fatigue, nausea, lightheadedness, chest pain, indigestion) 4. Classic symptoms (chest pressure, sweating, chest discomfort, shortness of breath, nausea, chest pain) 5. Pain and discomfort (chest pressure, shoulder pain, chest discomfort, arm pain, chest pain) 6. Chest symptoms only (chest pressure, chest discomfort, chest pain)
k-means Cluster Analysis	Three clusters (optCluster)	1. Low symptom burden (chest pain was only symptom with > 40% probability) 2. Chest symptoms (chest pressure, chest discomfort, chest pain) 3. Classic symptoms (chest pressure, shoulder pain, sweating, chest discomfort, shortness of breath, arm pain, fatigue, nausea, lightheadedness, chest pain)
Latent Class Analysis without covariates	Three classes (clusters) (Latent Gold)	1. Low probability symptoms (no symptoms have a >50% probability of occurring) 2. Chest symptoms (chest pressure, chest discomfort, chest pain) 3. Heavy symptom burden (chest pressure, shoulder pain, sweating, chest discomfort, shortness of breath, arm pain, fatigue, nausea, lightheadedness, chest pain)
Latent Class Analysis with covariates	Four classes (clusters) (Latent Gold	1. Chest symptoms (chest pressure, chest discomfort) 2. Heavy symptom burden (chest pressure, shoulder pain, chest discomfort, shortness of breath, arm pain, fatigue, chest pain) 3. Classic symptoms (chest pressure, shortness of breath, fatigue, nausea, lightheadedness, chest pain) 4. Low symptom burden (no symptoms have a > 50% probability of occurring)

Note. PCA = principal components analysis; EFA = exploratory factor analysis; CFA = confirmatory factor analysis; SAS = Statistical Analysis Software; SPSS = Statistical Package for the Social Sciences.