If I want to conduct a research about the effects of MALL on students' reading and listening skills, what kind of specific dependent variables for reading and listening skills respectively can I assess?
To me, as a thought, the question would not be which variables can be assessed as (dependent) outcome variables of an L2 learning intervention. Any trait (e.g., L2 motivation) or knowledge-based skill (e.g., L2 listening comprehension) of a student could (theoretically) be changed as a result of teaching. I would rather ask myself which skills I expect to change through the L2 teaching based on the available earlier theory. Scientifically speaking, what you are ultimately trying to do (at least in my opinion) is to validate or falsify existing assumptions about L2 learning in the theory, so that this theory may become an increasingly valid/true account of student L2 learning. Or, in brief, I would assess those skills which earlier research has pointed out as plausible outcome variables for MALL interventions.
Phonological coding tasks - "Tasks that tap the ability to identify and manipulate units of oral language parts (words, syllables, onsets and rimes, and phonemes) and phonological codes retrieval efficiency". For example: "Identify the rhyme of words; Identify initial sounds or final sounds in words; Identify medial sounds in words; Segment words into their component syllable/sound; delete/add sounds from/to words; Sound blending; Name letters/digits/colors/objects rapidly".
Decoding tasks - "Tasks that tap the ability to translate written language into speech with accuracy and fluency". For example: "Real word recognition, Non-word reading; reading word list; Accuracy/fluency of passage/sentence reading".
Comprehension - "Tasks that require individuals to comprehend a passage in either oral format (listening comprehension) or written format (reading comprehension)". For example: "Nelson Denny Reading Comprehension; Woodcock Reading Mastery Tests-Reading Comprehension; Gray Oral Reading Comprehension Tests; The Peabody Individual Achievement Test- Reading Comprehension".
I got this information from the article:
Article A Meta-Analysis on the Relation Between Reading and Working Memory