Characteristics of included studies
| Study lead author, year, country | RCT type | Participants randomised, n; mean age, years; female,% | Participants analysed (ITT), n | Mean UTIs in past 12 months, n | Intervention volume; frequency; duration (additives) | Comparator volume; frequency; duration (additives) | Duration of follow-up, months |
|---|---|---|---|---|---|---|---|
| De Leo, 2017, Italy15 | Two arm, parallel | 150; 48; 100 | Intervention: 100 Comparator: 50 | 8.6 | 250 ml;a daily during first 10 days of the month; 3 months | n/a; 3 months | 3 |
| Ferrara, 2009, Italy21 | Three arm, parallel | 84; 7.5; 100 | Intervention: 28 Comparator 1: 27 Comparator 2: 29 | >1b | 250 ml;c daily; 6 months | Comparator 1: 100 ml;d 5 days a month; 6 months Comparator 2: not reported; 6 months | 6 |
| Handeland, 2014, Norway18 | Two arm, crossover, cluster RCT | 236; 85; 67.8 | Intervention: 110 Comparator: 126 | 0.2e | 233 ml;f,g daily; 3 months then 156 ml;h daily; 3 months | 89 ml;h daily; 3 months then 78 ml;g daily; 3 months | 6 |
| Hooton, 2018, Bulgaria7 | Two arm, parallel | 140; 35.7; 100 | Intervention: 70 Comparator: 70 | 3.3 | 1500 ml;i daily; 12 months | No intervention; 12 months | 12 |
| Kontiokari, 2001, Finland19 | Three arm, parallel | 150; 30; 100 | Intervention: 50 Comparator 1: 50j Comparator 2: 50 | 6 | 250 ml;c daily; 6 months | Comparator 1: 100 ml drink;d 5 days a month; 12 months Comparator 2: no intervention (control) | 12 |
| Kranjčec, 2014, Croatia20 | Three arm, parallelk | 205;l 49; 100 | Intervention: 103 Comparator: 102 | 2m | 200 ml water;n daily; 6 months | No intervention; 6 months | 6 |
| Temiz, 2018, Turkey16 | Three arm, parallel | 60; 64; 31.7 | Intervention: 20 Comparator 1: 20 Comparator 2: 20 | 68.3%o | Recommended 2–3 L of water a day (which translates to 1–2 L above baseline, given estimates of baseline consumption of approx. 1.1 L (Hooton 2018)7 | Comparator 1: One capsule;p twice a day; 3 months Comparator 2: no intervention; 3 months | 3 |
| Stapleton, 2012, US (not meta-analysed as groups amalgamated in analyses)17 | Four arm, parallel | 186; 25; 100 | Intervention 1: 63 Intervention 2: 62 Comparator 1: 31 Comparator 2: 30 | 1.95 | Intervention 1:q,r, 4 oz (∼120 ml); daily; 6 months Intervention 2: 8 oz (∼240 ml); daily; 6 months | Comparator 1:s 4 oz (∼120 ml); daily, 6 months Comparator 2: 8 oz (∼240 ml); daily; 6 months | 6 |
↵a One glass of water with one Kistinox Forte sachet containing cranberry, propolis extract, and D-mannose.
↵b Inclusion criteria specified that history of >1 UTI required.
↵c Cranberry juice contained 7.5 g of cranberry concentrate and 1.7 g of lingonberry concentrate in 50 ml of water; the families were allowed to add 200 ml of unsweetened water to the 50 ml of concentrate.
↵d Lactobacillus GG drink containing 4 × 10^7 CFU of Lactobacillus GG/100 ml.
↵e Three-month baseline period.
↵f All four arms were offered 300 ml fluid (chokeberry juice versus placebo) but consumed varying amounts; fluid volume consumed reported.
↵g Placebo drink matching the black chokeberry juice as closely as possible in terms of colour, taste.
↵h Chokeberry juice from concentrate.
↵i In addition to usual water consumption.
↵j One omitted due to antibiotic prophylaxis.
↵k Antibiotic arm (nitrofurantoin) excluded from analysis.
↵l In total, 308 participants when antibiotic arm included.
↵m Median episodes reported in past 6 months.
↵n With 2 g D-mannose.
↵o Percentage of participants with UTI history; patients were included in study if they had undergone ileal conduit diversion.
↵p One capsule contains 400 mg cranberry with 18% proanthocyanidins (9 mg).
↵q Juice contained 27% cranberry juice and sucralose (Splenda).
↵r Study reported all outcomes as intervention (4 oz and 8 oz cranberry juice) versus comparator (4 oz and 8 oz placebo drink).
↵s Placebo drink of similar colour and taste to intervention but did not contain cranberry juice. ITT = intention to treat. n/a = not applicable. RCT = randomised controlled trial. UTI = urinary tract infection.