4.2 Instruments
Protocol Analysis the coding process was conducted by two of the
experimenters who coded the protocols independently according to clear operational
definitions of the categories. We in clued in the analysis only those activities that the
experimenters identified beyond any reasonable doubt as corresponding to one of the
content categories. Utterances were included only when both judges agreed
independently or after consultation that they represented self-explanation or control
activities. We measured coding reliability by calculating the two independent judges’
agreement on the categories. Validity and reliability.