The application of comprehension skills as a general cognitive ability has long been discussed in the literature on second language reading comprehension. To trace second language reading comprehension difficulties back to the text or reader attributes, the present study investigates the optimum load of linguistic and non-linguistic components of second language reading ability. The study followed a quantitative method of research, and the data were collected on the performance of 164 Iranian foreign language learners with different educational backgrounds. A group of Teaching English as a Foreign Language (TEFL) experts provided feedback on the specifications of the sample test items based on the Comprehensive Taxonomy of Reading Sub-skills (CTRS) derived from major taxonomies in the literature. Applying exploratory factor analysis and correlational computations, the results revealed that although the items were all convergent to measure the same latent construct, items aimed at measuring general cognitive comprehension skills had more contribution to the overall test scores. Teachers at both language institutes and ministry of education, test developing organizations, and students who seek to gain more success in reading comprehension examinations can benefit from this study feedback. تفاصيل المقالة