Table 5 Trials involving cryotherapy, surgical and combination therapy of genital warts

Reference	Patients	Design	Clearance	Recurrence/side effects
Stone KM, 1990 ^30	450	Randomized Control	Surgical excision showed complete clearance of warts in 94% and 71% after 6 weeks and 3 months	Recurrence
Simmons, PD 1981 ^31	42	Randomized Control	No significant difference over 3 months follow-up comparing cry therapy versus electrocautery	No data
Eron et al, 1993 ^33	97	Randomized control, double blind	Interferon alpha-2a had no benefit as an adjuvant to cryotherapy.	28% of interferon recipients and 43% of placebo recipients experienced recurrences. At six months follow-up, 69% interferon and 73% placebo recipients experienced recurrences.
Handley et al1991 ^34	91	Randomized control	At eight weeks subcutaneous IFN alpha 2a combined with cryotherapy showed 60.7% clearance versus 67.9% clearance with cryotherapy alone.	Recurrence at three months was 50% and 37.5% of patients in the IFN and placebo groups respectively
Abdullah et al 1993 ^35	86	Randomized controlled	86% clearance of warts in patients who received cryotherapy vs 70% of patients who received trichloracetic acid.	No data on recurrences. Ulcerations at the site of application developed in 30% of the TCA treated patients
Damstra et al 1991 ^36	134	Clinical trial	Showed clearance in 83% within 4 weeks and 96% after 6 weeks with cryotherapy versus 13% and 45% after 4 weeks and 6 weeks, respectively in the control	No data
Godley et al 1987 ^37	130	Randomized Control	Showed clearance in 88% of patients treated with cryotherapy versus 81% of those treated with TCAA	Recurrence found in 36% of patients treated with TCAA and in 39% of those treated with cryotherapy.