The following studies investigated the effect of treatments on patients following total knee replacement surgery using the following outcomes:

Study A: Examined the effect of early mobilisation on active range of knee extension (via goniometry)

Study B: Examined the effect of continuous passive mobilisation on knee pain (via 1-5 Likert scale questionnaire)

Study C: Examined the effect of different forms of analgesia on knee pain (via 0-10 visual analogue scale)

Study D: Examined the effect of a multidisciplinary 'care bundle' on quality of life (Short-Form-36 questionnaire)

Study E: Examined the effect of more intensive physiotherapy on knee swelling (measured circumference, cms)

Study F: Examined the effect of TENS on subjective measures of knee pain (custom questionnaire, score range 0-100).

It would be appropriate to calculate an effect size to summarise ('pool') results from which of the above 6 studies?