Smith 1989.

Study characteristics
Methods	Recruitment period: not reported Outcomes: bone pain, analgesia consumption Pain assessment tool: numerical analogue scales linear analogue scales bone pain rating scale (investigator) Randomization: intervention vs control
Participants	Eligibility criteria: prostate cancer metastatic to bone documented by bone scan 1 site of bone pain requiring analgesics caused by bone metastasis no radiation therapy within 1 month before study enrollment and during treatment period Exclusion criteria: serum creatinine > 2.5 mg/dL Participants randomized: 57 randomized, 14 intervention I (etidronate IV and etidronate orally), 14 intervention II (etidronate IV and placebo orally), 15 intervention III (placebo IV and etidronate orally), 14 control (placebo IV and placebo orally) Mean age: not reported Country of participants: not reported
Interventions	Previous interventions: all participants underwent hormonal therapy with no chance of hormonal therapy within 2 months before study enrollment Interventions during study period: intervention I: sodium etidronate 7.5 mg/kg IV daily for 3 days following sodium etidronate 200 mg orally twice a day intervention II: sodium etidronate 7.5 mg/kg IV daily for 3 days following 1 placebo tablet orally twice a day intervention III: placebo IV daily for 3 days following sodium etidronate 200 mg orally twice a day control: placebo IV daily for 3 days following 1 placebo tablet orally twice a day
Outcomes	Reported and analyzed in this review: none
Funding sources	Funding sources: not reported
Declarations of interest	Conflicts of interest: not reported
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information on sequence generation
Allocation concealment (selection bias)	Unclear risk	Insufficient information on allocation concealment
Blinding of participants and personnel (performance bias) Blinding of participants	Unclear risk	Placebo‐controlled trial, no further information on blinding
Blinding of participants and personnel (performance bias) Blinding of personnel	Unclear risk	Insufficient information on blinding of participants and personnel
Blinding of outcome assessment (detection bias) Outcomes subjective to participants	Unclear risk	No information on blinding of outcome assessors
Incomplete outcome data (attrition bias) Patient‐reported outcomes (other than safety data)	High risk	"Six patients [...] were considered unevaluable because they failed to complete 1 month of treatment."
Selective reporting (reporting bias)	Unclear risk	No study protocol available.
Other bias	High risk	No statistical analysis of observed results