Ferruggiari 2012.
| Methods | 3‐group non‐RCT comparing peppermint vapour, saline vapour and ondansetron to treat PON | |
| Participants | 70 non‐pregnant female surgical patients (23 peppermint/22 saline/25 ondansetron) > 18 years undergoing a surgical procedure at a suburban community hospital. Exclusionary criteria were olfactory sensory loss, allergy to peppermint, asthma, chronic obstructive pulmonary disease, or chronic respiratory conditions Setting: community hospital, USA |
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| Interventions | Peppermint oil or normal saline placed on identical size gauze squares and sealed in zip‐lock plastic bags. Treatment administered on initial complaint of nausea in PACU. Aromatherapy group participants instructed to take one inhalation from opened bag. Ondansetron group received 4 mg IV. A VAS was used to rate nausea at the first complaint; at 5 min after intervention; and, if nausea persisted, at 10 min after intervention | |
| Outcomes | Nausea severity at 3 and 5 min (and, if nausea persisted, at 10 min after intervention) as measured by 200 mm VAS (0 = no nausea, 200 = worst possible nausea) | |
| Notes | Confirmation received from study authors that while a 200 mm VAS was used to measure nausea, the results were converted to centimetres (i.e. 20 cm scale, 0‐20) in the published report. No information on funding sources | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | High risk | "For those receiving inhalation, the investigators randomly selected a sealed zip lock bag from a box containing bags of both peppermint and saline aromas." Comment: not done: study is CCT |
| Allocation concealment (selection bias) | High risk | Comment: not done: study is CCT |
| Blinding of participants and personnel (performance bias) All outcomes | Unclear risk | Comment: probably not done: no statement addressing blinding, although peppermint and saline treatments appeared identical & stored in same box, investigators would have been unblinded to treatment when bag opened due to odour |
| Blinding of outcome assessment (detection bias) All outcomes | Unclear risk | Comment: no blinding of assessors described. Study investigators appear to have assessed outcomes |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Comment: no attrition described. Results of all participants reported |
| Selective reporting (reporting bias) | Low risk | Comment: all outcomes stated in the paper also have data reported |
| Other bias | Unclear risk | Comment: no other sources of bias apparent |