evidence.

500 couples in five countries timed sex with a stopwatch for four weeks. The median time from penetration to ejaculation was 5.4 minutes, and only about 2.5% of men were under one minute.

Why the Last Longer program starts with a number instead of a pep talk.

Waldinger MD, Quinn P, Dilleen M, et al. A multinational population survey of intravaginal ejaculation latency time. J Sex Med. 2005;2(4):492-497. PubMed

Sex therapists rated 3 to 7 minutes of intercourse “adequate” and 7 to 13 “desirable”, and recommended telling the public that 3 to 13 minutes is normal, to prevent needless distress.

The range Raisin shows you in week one.

Corty EW, Guardiani JM. Canadian and American sex therapists’ perceptions of normal and abnormal ejaculatory latencies. J Sex Med. 2008;5(5):1251-1256. PubMed

In 52,588 US adults, 95% of heterosexual men said they usually orgasm during sex, against 65% of heterosexual women; women were more likely to orgasm when the encounter included deep kissing, manual and oral stimulation, not only longer intercourse.

Why Better Together moves time toward touch and talk rather than toward the stopwatch.

Frederick DA, John HKS, Garcia JR, Lloyd EA. Differences in orgasm frequency among gay, lesbian, bisexual, and heterosexual men and women in a U.S. national sample. Arch Sex Behav. 2018;47(1):273-288. PubMed

Of 12,133 men surveyed in the US, Germany and Italy, about one in five said they finish too soon, and only 9% of those had ever raised it with a doctor.

Why Raisin is private by design, and why it asks the hard questions so you do not have to.

Porst H, Montorsi F, Rosen RC, et al. The Premature Ejaculation Prevalence and Attitudes (PEPA) survey. Eur Urol. 2007;51(3):816-823. PubMed

The International Society for Sexual Medicine’s guideline defines lifelong premature ejaculation as finishing within about a minute, sets out the graduated stop-start sequence (solo, then partner’s hand, then still intercourse, then movement), and rates behavioral therapy as useful, with the best results when combined with other treatment.

The spine of the Last Longer program, and the reason the app tells you when to see a doctor about other options.

Althof SE, McMahon CG, Waldinger MD, et al. An update of the International Society of Sexual Medicine’s guidelines for the diagnosis and treatment of premature ejaculation. Sex Med. 2014;2(2):60-90. Full text

A systematic review of ten randomized trials: stop-start and squeeze packages beat a waiting list by several minutes in the best trials, but a web-only program of lessons did not move the stopwatch at all.

Why Raisin makes you do timed physical practice instead of only reading about it.

Cooper K, Martyn-St James M, Kaltenthaler E, et al. Behavioral therapies for management of premature ejaculation: a systematic review. Sex Med. 2015;3(3):174-188. Full text

40 men who finished within a minute did 12 weeks of pelvic-floor rehabilitation; 33 gained control, and the average time rose from about half a minute to about two and a half minutes. This was clinic-based with biofeedback, so expect smaller gains from home training.

Why the pelvic-floor drill teaches you to relax the muscle as arousal climbs, not only to squeeze it.

Pastore AL, Palleschi G, Fuschi A, et al. Pelvic floor muscle rehabilitation for patients with lifelong premature ejaculation: a novel therapeutic approach. Ther Adv Urol. 2014;6(3):83-88. PubMed

In the lab, men with erection difficulties differed from men without in where their attention went: watching and judging themselves instead of feeling what was happening, and that self-monitoring blocks arousal.

The loop Stronger and Calmer trains you out of, with attention drills and the wax-and-wane exercise.

Barlow DH. Causes of sexual dysfunction: the role of anxiety and cognitive interference. J Consult Clin Psychol. 1986;54(2):140-148. APA PsycNet

A randomized trial of 55 men with erection difficulties: pelvic-floor training with biofeedback improved erections significantly more than lifestyle advice alone, and at six months 40% had normal function back and another 35% had improved.

Raisin’s pelvic-floor protocol is this trial’s: three ten-second holds, three positions, morning and evening. The app cannot give you biofeedback, and says so.

Dorey G, Speakman M, Feneley R, et al. Randomised controlled trial of pelvic floor muscle exercises and manometric biofeedback for erectile dysfunction. Br J Gen Pract. 2004;54(508):819-825. Full text

Ten men whose erections were unreliable in some situations but not others did four weeks of mindfulness training with daily home practice; six months later, erections and satisfaction had improved by a moderate to large amount. Small study, no control group.

The attention and body-scan drills, offered as promising rather than proven.

Bossio JA, Basson R, Driscoll M, Correia S, Brotto LA. Mindfulness-based group therapy for men with situational erectile dysfunction: a mixed-methods feasibility analysis and pilot study. J Sex Med. 2018;15(10):1478-1490. PubMed

78 men were randomized to seven weeks of guided internet cognitive behavioral therapy or an online discussion group; the difference was small at the end of the program and large six months later.

Why Raisin keeps checking in after the program ends. Skills need time in the field.

Andersson E, Walén C, Hallberg J, et al. A randomized controlled trial of guided Internet-delivered cognitive behavioral therapy for erectile dysfunction. J Sex Med. 2011;8(10):2800-2809. PubMed

Pooling 14 studies and 92,757 men, erection difficulties predicted about 44% higher risk of a cardiovascular event and 62% higher risk of a heart attack in the years that followed, with the relative risk higher in younger men.

Why the app treats persistent erection trouble as a reason to see a doctor, and frames it as an early warning you can act on.

Vlachopoulos CV, Terentes-Printzios DG, Ioakeimidis NK, Aznaouridis KA, Stefanadis CI. Prediction of cardiovascular events and all-cause mortality with erectile dysfunction: a systematic review and meta-analysis of cohort studies. Circ Cardiovasc Qual Outcomes. 2013;6(1):99-109. PubMed

The American Urological Association’s guideline says men with erection difficulties should be told it is a risk marker for heart disease, that lifestyle change may help, that validated questionnaires can track progress, and that an approved oral medication is an option a clinician can discuss.

Raisin follows it the only way an app can: explain, track, and refer. It never suggests a drug or a dose.

Burnett AL, Nehra A, Breau RH, et al. Erectile Dysfunction: AUA Guideline. J Urol. 2018;200(3):633-641. AUA

Across 145 studies and 88,577 men, about half of men with diabetes had erection difficulties, and diabetes raised the odds more than threefold.

Why the safety screen asks about thirst, urination and weight loss.

Kouidrat Y, Pizzol D, Cosco T, et al. High prevalence of erectile dysfunction in diabetes: a systematic review and meta-analysis of 145 studies. Diabet Med. 2017;34(9):1185-1192. PubMed

241 men with erection difficulties were randomized to a structured app (exercise, pelvic-floor training, psychological support and education) or a control; the app group’s erection score improved by 4.5 points against 0.2, a clinically meaningful difference.

The model Raisin copies: several components, daily structure, not a single trick.

Kliesch S, Cremers JF, Krallmann C, et al. App-based therapy of erectile dysfunction using a digital health application (EDDIG study): a randomized, single-blind, controlled trial. Eur Urol Focus. 2024. PubMed

A meta-analysis of 12 randomized trials with 952 participants: internet and mobile programs for sexual problems had a real but small effect for men, and most studies had high dropout.

The honest ceiling for lessons alone, and why Raisin is built around practice and short sessions rather than reading.

Zarski AC, Velten J, Knauer J, Berking M, Ebert DD. Internet- and mobile-based psychological interventions for sexual dysfunctions: a systematic review and meta-analysis. NPJ Digit Med. 2022;5:139. Full text

The clearest description of sensate focus, used by most sex therapists: structured touching sessions where the point is noticing temperature, texture and pressure for your own interest, with arousal and orgasm off the table at first, then a staged return to sex.

The partner sessions in Better Together and Stronger and Calmer follow this protocol, stage by stage.

Weiner L, Avery-Clark C. Sensate Focus: clarifying the Masters and Johnson’s model. Sex Relat Ther. 2014;29(3):307-319. PDF

Across 48 studies, couples who talk about sex have better desire, arousal, orgasm and erections, and the link is strongest in long relationships.

Why every program ends with a script for one conversation.

Mallory AB, Stanton AM, Handy AB. Couples’ sexual communication and dimensions of sexual function: a meta-analysis. J Sex Res. 2019;56(7):882-898. PubMed

In a US probability sample of 1,055 women, fewer than one in five said intercourse alone was enough for orgasm, and preferences for touch varied widely.

The reason the app’s advice on partner pleasure comes down to one word: ask.

Herbenick D, Fu TJ, Arter J, Sanders SA, Dodge B. Women’s experiences with genital touching, sexual pleasure, and orgasm. J Sex Marital Ther. 2018;44(2):201-212. PubMed

A meta-analysis found erection difficulties and depression run in both directions: each raises the odds of the other.

Why the check-in asks about mood, and why a low answer brings up the crisis lines.

Liu Q, Zhang Y, Wang J, et al. Erectile dysfunction and depression: a systematic review and meta-analysis. J Sex Med. 2018;15(8):1073-1082. PubMed

An erection lasting more than four hours is a medical emergency; tissue damage begins within hours and the risk of permanent erection problems rises sharply with delay.

The one line on the safety page that is in bold, in a black box, at the top.

Urology Care Foundation. Priapism: symptoms, diagnosis and treatment. urologyhealth.org

Free, confidential support in the US, all day, every day, by call, text or chat.

Shown by the app whenever a check-in or coach message suggests you might be at risk.

988lifeline.org