Table 4.

Quality assessment checklist (Jadad scale tool).

Author	Randomization Reported?	Random sequence generation? (selection bias)	Allocation Concealment (selection bias)	Blinding reported? Who is blinded? (performance/ detection bias)	Withdrawals/ dropouts described?	Percentage of Follow up (Attrition bias)
1-Wolf et al	Yes	Yes	By blocks	No	None reported	100
2-Sahota et al	Yes	YesBy random numbers	Yes.Central web unit at the university.	Yes,Researchers and analyst	5.6% in intervention group	93%
3-Shorr et al	Yes	Yes.By random numbers	By independent statistician	Yes	None reported	100
4-Kwok et al	Yes	YesBy random numbers	Yes.Sealed envelopes.	Yes	None reported	100