Research transparency
The Sleep Mobility Report
We want better evidence about what it is like to reposition yourself in bed at home. Most published slide-sheet research studies caregiver tasks in healthcare settings. Our 2026 survey is a small, preregistered attempt to describe the home experience among Snoozle customers — not a clinical trial and not proof that a product causes an outcome.
This page describes the survey before results are interpreted. We will publish the results even if they are neutral or disappointing.
Important correction
An older version of this page presented unverified survey statistics and gave interpretation bands for the Bed Mobility Difficulty Index (BMDI). Those interpretations have been removed. The BMDI is an investigator-developed exploratory questionnaire. It has not been clinically validated, has no established diagnostic thresholds and should not be used to decide what treatment, device or movement technique a person needs.
Why run a home survey at all?
The published evidence gives us useful mechanical background. NICE describes slide sheets as low-friction systems that make moving or repositioning a person easier, and controlled studies have found lower caregiver force, muscular demand or perceived exertion with friction-reducing systems compared with ordinary sheets in some patient-handling tasks.
That evidence is valuable, but it answers a different question from the one Snoozle users face at night. A caregiver repositioning another person is not the same task as a person independently changing position while half asleep. We therefore treat the clinical handling literature as mechanism/background evidence, not as a direct Snoozle outcome study.
Background sources: NICE HTG745, Theou et al., Larson et al. and Wiggermann et al..
What is the BMDI?
The Bed Mobility Difficulty Index (BMDI) is the name we gave the six-item exploratory composite used in this survey. Each item is scored from 0 to 3 and the preregistered analysis reports the distribution, mean and median of the 0–18 total as descriptive data.
The six questions ask about: how often a respondent changes position, how often turning wakes them, pain during the movement, perceived effort, feeling gripped by the mattress surface, and morning stiffness/soreness associated with staying in one position.
What the BMDI is not
- It is not a validated clinical instrument.
- It is not a diagnostic score.
- There are no evidence-based mild/moderate/severe cut-offs.
- A higher score does not prove friction is the cause.
- A score does not establish that Snoozle or any other product will help.
The preregistered 2026 survey
The survey was preregistered before responses were collected. The instrument and analysis plan are fixed in the repository and mirrored on OSF. The plan uses descriptive statistics only; it does not specify hypothesis tests or clinical thresholds.
- Population: Snoozle customers invited from the customer email list.
- Anonymous: the survey endpoint is designed not to store names, emails, order IDs or IP addresses with responses.
- Exploratory BMDI: six 0–3 items are summed to a 0–18 descriptive total.
- Product question: respondents separately report whether turning has felt much easier, somewhat easier, unchanged or harder since using Snoozle, plus duration of use.
- Publication commitment: results and limitations will be published regardless of direction.
Public preregistration: OSF 9pc35. The repository copy is the auditable record used by this site.
Conflict of interest
This matters enough to state plainly: the investigator founded Snoozle, the respondents are Snoozle customers, and one survey item asks respondents about their experience since using Snoozle. That creates obvious selection and commercial conflicts. The survey can describe what this customer sample reports; it cannot establish a causal product effect or represent everyone who has difficulty moving in bed.
How we will report results
We will follow the preregistered descriptive analysis: response count and response rate; distributions and summary statistics for each BMDI item and the exploratory total; condition-group summaries only where the preregistered minimum group size is met; and the Snoozle experience question reported separately from the BMDI.
Results will be accompanied by the important limitations: self-report, self-selection, a customer-only sample, no control group and no clinical validation of the BMDI. If the data are messy or do not show the pattern we expected, that is part of the result rather than a reason to hide it.