E1: SMS reminders raise attendance
RR 1.14 (1.03–1.26), 67.8%→78.6%; RR 1.08 without one outlier trial; SMS ≈ phone (RR 0.99)
Strength: strong · Type: peer-reviewed, transferable · Date: 2013 · Scored in: R1
Source: Cochrane CD007458
Evidence library · reviewed 2026-10-21
23 sources behind our Policy Score, Policy Builder and guides: 9 peer-reviewed, 10 vendor figures. Each one says what it shows, how strong it is, and which scoring rule uses it.
Every source page was opened and checked unless noted. Transferable = healthcare or restaurant evidence, not salons. Vendor = a platform's own data with no published method. No peer-reviewed salon or beauty no-show study was found. Conflicting evidence does not change Policy Score points until it is reviewed.
Machine-readable copy: /evidence.json (same data, updated with this page).
| Rule | What scores | Max points | Strength | Evidence |
|---|---|---|---|---|
| R1 | Automated reminders for every appointment | 30 | Strong (transferable from healthcare) | E1, E2 |
| R2 | Two reminders beat one | 12 | Moderate (transferable from healthcare) | E3, E2 |
| R7 | Reminders state the specific value of the slot | 10 | Weak–moderate (transferable; 1 RCT found an effect, a 2026 replication found none overall) | E6, E23 |
| R3 | A payment commitment at booking (size not scored) | 15 | Weak–moderate (uncontrolled vendor data; the only RCT found no effect) | E10, E11, E13, E7 |
| R6 | Target friction at new clients, past no-shows and far-ahead bookings | 12 | Moderate (transferable from healthcare) | E4, E5, E3 |
| R5 | Waitlist / backfill for cancellations | 11 | Weak–moderate (vendor data) | E16, E17 |
| R4 | Written policy shown at booking, notice window ≥24h | 10 | Weak (no comparative evidence) | none (no comparative study) |
| R8 | Confirmation requests: not scored | 0 | Weak | E18 |
RR 1.14 (1.03–1.26), 67.8%→78.6%; RR 1.08 without one outlier trial; SMS ≈ phone (RR 0.99)
Strength: strong · Type: peer-reviewed, transferable · Date: 2013 · Scored in: R1
Source: Cochrane CD007458
No-shows 21%→15% (RR 0.75); multiple > single; voice > text
Strength: strong · Type: peer-reviewed, transferable · Date: 2016 · Scored in: R1, R2
Source: Robotham, BMJ Open
Missed: 3d+1d 4.4% vs 1d 5.3% vs 3d 5.8% (n=54,066). High-risk: 20.5% vs 24.2–25.0%
Strength: moderate · Type: peer-reviewed RCT, transferable · Date: 2018 · Scored in: R2, R6
Source: Steiner, AJMC
105 studies; mean 23.0% (4.0–79.2%); high lead time and prior no-show history the most common determinants
Strength: moderate · Type: peer-reviewed review, transferable · Date: 2018 · Scored in: R6
Source: Dantas, Health Policy
7.8%→3.9% after the maximum booking horizon was cut from 28 days to 1 day (one practice)
Strength: moderate · Type: peer-reviewed, transferable · Date: 2021 · Scored in: R6
Source: Margham, BJGP
11.1%→8.4% (OR 0.74) in Trial 1; Trial 2 kept the cost message as reference (8.2%) with no control arm, so it is not a replication (see E23); vague "general cost" wording 9.9%; social-norm message raised cancellations from 8.8% to 10.5%
Strength: moderate · Type: peer-reviewed RCTs, transferable · Date: 2015 · Scored in: R7
Source: Hallsworth, PLoS ONE
€34 fine: 5% vs 5% (130/3,333 vs 131/3,413)
Strength: moderate · Type: peer-reviewed RCT, transferable · Date: 2018 · Scored in: R3
Source: Blæhr, BMJ Open (BMJ site returned 403; abstract read via SDU)
Both fell significantly (p<.001); 6 hotel restaurants
Strength: weak · Type: dissertation, transferable · Date: 2015 · Not scored
Source: Hernandez, Walden
£50 deposit: "zero no shows" for about a year; cutting it to £5 brought them back (one restaurant)
Strength: weak · Type: anecdote · Date: 2023 · Not scored
Source: Drinks Business
5.4%→1.9% (−65%); typical deposit is 30% of price. Same year in trade press: "−47%"; UK no-shows 5% (counties 4.1–9.4%)
Strength: weak · Type: vendor · Date: 2021 · Scored in: R3
Source: Phorest, Estetica
−29% cancels/no-shows vs no deposit
Strength: weak · Type: vendor · Date: 2024 · Scored in: R3
Source: Kitomba
"89% fewer no-shows" / "up to 90%"; reminders "up to 30%"; ~10% late cancels + no-shows
Strength: weak · Type: vendor · Date: 2022–23 · Not scored
Source: Estetica, Fresha
Square −21% cancels/no-shows; 5% of sellers had fees on in 2021, "nearly tripled" by 2023. Booksy −20% cancellations, "no significant impact on bookings"
Strength: weak · Type: vendor · Date: 2024 / 2021 · Scored in: R3
Source: Square, Booksy
GlossGenius +32% successful appointments; Zenoti "95% drop"; Boulevard "up to 71%" (first 90 days)
Strength: weak · Type: vendor · Date: 2025 / 2026 / 2022 · Not scored
Source: GlossGenius, Zenoti, Boulevard
All 3.8%; barbers 21.16%; brows/lashes 6.55%; beauty 3.59%; nails 3.55%; hair 3.16%
Strength: moderate (sample disclosed) · Type: vendor, via trade press · Date: May–Aug 2024 · Not scored
Source: Professional Beauty
Salons 8/3%; nails 16/1%; barbers 2/4%; membership spas 14/1%; non-membership spas 11/1%; medspas 16/5%
Strength: moderate · Type: vendor · Date: 2024 data · Scored in: R5
Source: Zenoti
GlossGenius waitlist fills "12% more cancellations". Zenoti, 2025 data: nails cancels 16%→11% while no-shows rose 1%→4%
Strength: weak · Type: vendor · Date: undated / 2025 · Scored in: R5
Source: GlossGenius, Zenoti
RR 1.03 (0.95–1.12) for attendance vs standard care; 5 trials, Africa
Strength: weak · Type: peer-reviewed, transferable · Date: 2022 · Scored in: R8
Source: Ødegård, PLoS ONE
"50% deposit… drastically reduced… no shows"
Strength: weak · Type: anecdote · Date: undated · Not scored
Source: r/Esthetics (source page not opened by us; quoted from a secondary summary)
Canada, n=1,001 (online, weighted, MoE ±3.1): 53% call a barber/salon no-show fee justified; 8% missed a barber/salon appointment in the past year; 4% paid such a fee; 18–34s miss most (43% any appointment). Per person-year, not a per-booking no-show rate
Strength: moderate (acceptance only) · Type: independent poll · Date: 2024-08-07 (fieldwork Jul 5–7) · Not scored
Source: Research Co.
Clients who cancel: 62% give <24h notice; 22% cite forgetting. Owners: 56% lose <5% of monthly revenue, 29% 5–10%, 15% 11–20%
Strength: weak · Type: vendor survey · Date: pub. 2026-02-02 (data Dec 2025; ~200 businesses + 500 clients) · Not scored
Source: Fresha survey
June 2026, all shops on Reservia: client self-booked web cancel 17.61% but no-show 1.80% (n=206,014); staff-entered bookings 15.37% / 4.87% (n=144,018); external booking sites 9.47% / 4.14% (n=60,077). Same direction in all 6 segments (hair 17.24% vs 15.36% cancel). No-show = cancelled by the shop on the day
Strength: moderate (correlational; Japan) · Type: vendor platform data, full count, definitions disclosed · Date: data 2026-06 (pub. ~2026-08) · Not scored
Source: Reservia
Denmark, 1 hospital, 3 outpatient depts, 20,867 appointments (Oct 2019–Mar 2020), SMS ≤2 days before, wording rotated every 2 months (time-blocked, not randomised). Overall: neither cost nor social-norm wording reduced no-shows; cost wording raised advance cancellations 2.45%→3.42% (OR 1.41). By dept: social norm cut no-shows in Cardiology 5.23%→4.03% (OR 0.76); cost wording raised them in Endocrinology 3.94%→5.09% (OR 1.31). Men 5.13% vs women 3.62%
Strength: moderate (large n; not randomised) · Type: peer-reviewed quasi-experiment, transferable · Date: pub. 2026-04-23 (data 2019–20) · Scored in: R7
Source: Hansen et al., Behavioural Public Policy
The salon no-show letter
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