The Mattress Evidence & Clinical Studies Library

Spine & Chronic Back Pain The Lancet

Vol. 362, Issue 9396, pp. 1599-1604

Effect of Mattress Firmness on Chronic Low-Back Pain: A Randomised, Double-Blind Controlled Trial

By F. M. Kovacs, V. Abraira, A. Peña and 10 co-authors

Sample: N = 313 Study Type: Randomised Double-Blind Trial

• What was tested: 313 adults with long-term low back pain were randomly given either a firm or a medium-firm mattress. Neither the patients nor the people assessing them knew which one each person had.
• What the numbers showed: At 90 days, people on medium-firm mattresses had better odds of improvement in pain in bed (odds ratio 2.36) and in disability (odds ratio 2.10) than people on firm mattresses. For pain on getting up, the 90-day result was not statistically clear.
• What this means for you: For these patients, medium-firm did better than firm. The trial did not test modern foam or hybrid beds, or any brand you can buy today.

DOI: 10.1016/S0140-6736(03)14792-7 | The Lancet

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Orthopedic Bedding Review Journal of Orthopaedics and Traumatology

Vol. 22, Issue 1, Article 51

What Type of Mattress Should Be Chosen to Avoid Back Pain and Improve Sleep Quality? Review of the Literature

By G. Caggiari, G. R. Talesa, G. Toro, E. Jannelli, G. Monteleone and L. Puddu

Sample: 39 articles Study Type: Systematic Review

• What was tested: Orthopaedic researchers reviewed 39 articles on mattresses, sleep quality and low back pain in adults, published from 2000 to 2019.
• What the numbers showed: The review does not combine the studies into one number. The authors conclude that a medium-firm mattress promotes comfort, sleep quality and spinal alignment.
• What this means for you: The evidence leans toward medium-firm for non-specific low back pain. The authors note the studies differed and the type of back pain was often poorly defined.

DOI: 10.1186/s10195-021-00616-5 | Journal of Orthopaedics and Traumatology

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MRI Spine Alignment European Radiology Experimental

Vol. 7, Article 47

Effect of a Mattress on Lumbar Spine Alignment in Supine Position in Healthy Subjects: An MRI Study

By J. A. Vitale, S. Borghi, T. Bassani, C. Messina, L. M. Sconfienza and F. Galbusera

Sample: N = 20 Study Type: MRI Comparison

• What was tested: 20 healthy adults had MRI scans of the lower spine while lying on their backs, once on a medium-firm foam mattress and once on the rigid scanner table.
• What the numbers showed: On a medium-firm foam mattress, the lower back curve was 2.9 degrees larger and the tilt at the base of the spine 2.0 degrees larger than on a rigid table. The authors call these changes small but statistically significant.
• What this means for you: A mattress changes how your lower spine sits by a few degrees. The study tested one mattress, funded by its maker, and did not compare firmness levels or measure pain.

DOI: 10.1186/s41747-023-00361-w | European Radiology Experimental

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Pressure Mapping and Sleep PLoS ONE

Vol. 9, Issue 6, e99969

Effects of Interface Pressure Distribution on Human Sleep Quality

By Z. Chen, Y. Li, R. Liu, D. Gao, Q. Chen, Z. Hu and J. Guo

Sample: N = 16 Study Type: Randomized Crossover Lab Study

• What was tested: 16 healthy men slept one night on each of 4 mattresses in a sleep lab while a 684-sensor mat mapped body pressure and sleep sensors recorded their sleep.
• What the numbers showed: The two mattresses with middle-range pressure spread gave more deep sleep than a hard plank bed and got higher comfort and sleep quality ratings.
• What this means for you: Very concentrated and very even pressure both scored worse. The mattresses came from a company that employed several authors, and only 16 men took part.

DOI: 10.1371/journal.pone.0099969 | PLoS ONE

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Flame Retardants in Foam Environmental Science & Technology

Vol. 45, Issue 12, pp. 5323-5331

Identification of Flame Retardants in Polyurethane Foam Collected from Baby Products

By H. M. Stapleton, S. Klosterhaus, A. Keller, P. L. Ferguson, S. van Bergen, E. Cooper, T. F. Webster and A. Blum

Sample: 101 foam samples Study Type: Lab Survey

• What was tested: Scientists tested foam from 101 U.S. baby products, including car seats, changing pads and 13 portable crib mattresses, for flame retardant chemicals.
• What the numbers showed: 80 of 101 samples held an identified flame retardant. TDCPP was the most common, in 36% of samples.
• What this means for you: The study tested baby products bought mostly between 2000 and 2010, not adult mattresses, so it does not describe mattresses sold today.

DOI: 10.1021/es2007462 | Environmental Science & Technology

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Pillows and Neck Pain Journal of Pain Research

Vol. 3, pp. 137-145

Pillow Use: The Behavior of Cervical Stiffness, Headache and Scapular/Arm Pain

By S. J. Gordon, K. A. Grimmer-Somers and P. H. Trott

Sample: N = 106 Study Type: Randomized Home Trial

• What was tested: 106 healthy side sleepers tried 5 new pillows (polyester, regular foam, contour foam, feather and latex) for 1 week each at home and logged waking symptoms every day.
• What the numbers showed: On latex, 90.9% woke with no headache and 88.3% with no shoulder or arm pain, the best of any pillow. Feather did worst, and only 67.3% finished the feather week.
• What this means for you: Pillow filling made a difference for these healthy side sleepers. Contour foam did no better than regular foam. The study did not test mattresses.

DOI: 10.2147/JPR.S10880 | Journal of Pain Research

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Allergies & Dust Mites Journal of Allergy and Clinical Immunology

Vol. 111, Issue 2, pp. 408-414

House Dust Mite Allergen in US Beds: Results from the First National Survey of Lead and Allergens in Housing

By S. J. Arbes, R. D. Cohn, M. Yin, M. L. Muilenberg, H. A. Burge, W. Friedman and D. C. Zeldin

Sample: 831 homes Study Type: National Survey

• What was tested: A national survey collected dust from a bed in 831 U.S. homes in 1998 and 1999 and measured two dust mite allergens.
• What the numbers showed: 84.2% of homes had detectable mite allergen in a bed, 46.2% had 2.0 µg per gram or more, and 24.2% had 10.0 µg per gram or more.
• What this means for you: Mite allergen in beds is common, especially in older, more humid homes. The study did not test covers or mattress types.

DOI: 10.1067/mai.2003.16 | Journal of Allergy and Clinical Immunology

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Mattress Toppers & Athletes Scientific Reports

Vol. 10, Article 11805

Evaluations of Effects of Sleep Surfaces on Athletic Performance in Youth

By T. Maruyama, S. Sato, M. Matsumura, T. Ono, M. Nishida and S. Nishino

Sample: 74 athletes Study Type: Randomized Crossover

• What was tested: 74 male athletes aged 10 to 19 at a sports school slept 4 to 6 weeks on a high-rebound fiber topper and the same time on a memory foam topper or no topper.
• What the numbers showed: Sprint time (study I) and an agility drill (study II) were a little faster on the high-rebound topper. Long jump, sleep and reaction time did not change.
• What this means for you: Small, preliminary gains on a different test in each study. The topper maker funded it, and it did not test full mattresses.

DOI: 10.1038/s41598-020-68795-5 | Scientific Reports

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Pregnancy & Pelvic Pain International Journal of Women's Health

Vol. 13, pp. 1251-1260

Effects of a New Mattress and Pillow and Standard Treatment for Nightly Pelvic Girdle Pain in Pregnant Women: A Randomised Controlled Study

By C. Feldthusen, M. Fagevik Olsén, H. Ejnell and H. Elden

Sample: N = 66 Study Type: Randomised Controlled Study

• What was tested: 66 pregnant women with pelvic pain at night got standard treatment, and 34 of them also got a memory foam mattress and pillow, for 4 weeks.
• What the numbers showed: Nightly pain at the back of the pelvis fell 16.5 mm more (0 to 100 mm scale) in the mattress group, and sleep time rose 26 vs 14 minutes.
• What this means for you: Pressure-relieving support may ease pelvic pain at night, but only 44 women finished and one author owns the mattress design.

DOI: 10.2147/IJWH.S335977 | International Journal of Women's Health

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Spine & Bedding Designs Sleep Health

Vol. 1, Issue 4, pp. 257-267

Effect of Different Mattress Designs on Promoting Sleep Quality, Pain Reduction, and Spinal Alignment in Adults With or Without Back Pain: Systematic Review of Controlled Trials

By A. Radwan, P. Fess, D. James, J. Murphy, J. Myers, M. Rooney, J. Taylor and A. Torii

Sample: 24 trials Study Type: Systematic Review

• What was tested: Researchers reviewed 24 controlled trials published since 2000 on soft, medium-firm, firm and self-adjusted mattresses, plus mattress temperature.
• What the numbers showed: The trials were rated moderate to high in quality. The authors did not pool them into one number.
• What this means for you: The review favors a medium-firm, self-adjusted mattress for comfort, sleep and spinal alignment. It did not test any brand.

DOI: 10.1016/j.sleh.2015.08.001 | Sleep Health

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Mattress Age & Degradation Journal of Chiropractic Medicine

Vol. 8, Issue 1, pp. 1-8

Changes in Back Pain, Sleep Quality, and Perceived Stress After Introduction of New Bedding Systems

By Bert H. Jacobson, Ali Boolani and Doug B. Smith

Sample: N = 59 Study Type: Before-and-After Study

• What was tested: Researchers tracked 59 adults sleeping on their existing old mattresses (average age 9.5 years) for 28 days, then replaced them with new medium-firm bedding systems and measured symptoms for another 28 days.
• What the numbers showed: On the new beds, reported back pain fell by about 48% and sleep quality rose by about 55%. Two stress scores fell by 19.5% and 21.5%.
• What this means for you: The results fit the idea that an old mattress can make back pain and sleep worse, but there was no control group and the study was funded by the Better Sleep Council, a mattress industry group.

DOI: 10.1016/j.jcm.2008.09.002 | Journal of Chiropractic Medicine

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Active Spinal Support Work

Vol. 41, Suppl. 1, pp. 1274-1280

A Bed That Adjusts Its Support During the Night: Effect on Sleep

By D. Van Deun, V. Verhaert, T. Willemen, et al.

Sample: N = 11 Study Type: Sleep Lab Study

• What was tested: 11 normal sleepers spent nights in a sleep lab on a prototype bed with 8 comfort zones that adjusted overnight to keep the spine aligned.
• What the numbers showed: People rated their sleep better on the active support night. Lab recordings were mixed: a trend toward more deep sleep, but more of the lightest stage.
• What this means for you: Adaptive support shows some promise, but this was one small study of a lab prototype, not a mattress you can buy.

DOI: 10.3233/WOR-2012-0313-1274 | Work

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Fiberglass in Mattresses Int. J. Environ. Res. Public Health

Vol. 19, Issue 3, Article 1695

Fiberglass and Other Flame-Resistant Fibers in Mattress Covers

By J. Wagner, J. Fowles and T. Barreau (California Department of Public Health)

Sample: N = 4 Study Type: Lab Study of Mattress Covers

• What was tested: California Department of Public Health scientists bought 4 new mattresses and studied the layers of each cover under microscopes. They did not sample room air.
• What the numbers showed: Two of 4 new mattress covers had over 50% fiberglass in the inner sock, and up to 1% of it had moved into nearby fabric layers. None was seen on the outer surface.
• What this means for you: If your mattress has a zippered cover, do not take it off. From 1 January 2027, California bans textile fiberglass in new mattresses sold in the state.

DOI: 10.3390/ijerph19031695 | Int. J. Environ. Res. Public Health

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Mattress Fire Rule Code of Federal Regulations

In force July 1, 2007

Standard for the Flammability (Open Flame) of Mattress Sets: 16 CFR Part 1633

By U.S. Consumer Product Safety Commission

Sample: 3 specimens per prototype Study Type: Federal Safety Rule

• What was tested: A federal rule, not a study. Each mattress prototype is lit with two propane burners, top and side, and its heat output is measured for 30 minutes.
• What the numbers showed: To pass, peak heat release must stay at or below 200 kW, and total heat at or below 15 MJ in the first 10 minutes. All three specimens must pass.
• What this means for you: The rule does not require any particular fire barrier material. A pass tells you the limit was met, not what the barrier is made of.

Rule: 16 CFR Part 1633 | Code of Federal Regulations

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Heat, Humidity & Deep Sleep Sleep

Vol. 22, Issue 6, pp. 767-773

Effects of Humid Heat Exposure on Human Sleep Stages and Body Temperature

By K. Okamoto-Mizuno, K. Mizuno, S. Michie, A. Maeda and S. Iizuka

Sample: N = 7 Study Type: Sleep Lab Study

• What was tested: 7 healthy young men slept in a lab at 29°C or 35°C room temperature, each at 50% or 75% relative humidity.
• What the numbers showed: At 35°C and 75% humidity they woke more and had lower sleep efficiency and less deep and REM sleep than at 29°C.
• What this means for you: Hot, humid bedrooms can make sleep lighter. The study tested room air, not mattresses.

DOI: 10.1093/sleep/22.6.767 | Sleep

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Mattress Cooling & Sleep Clocks & Sleep

Vol. 7, Issue 4, Article 55

Under the Covers: The Effect of a Temperature-Controlled Mattress Cover on Sleep and Perceptual Measures in Healthy Adults

By S. Stevenson, H. Suppiah, T. Mündel and M. Driller

Sample: N = 34 Study Type: Randomised Crossover Study

• What was tested: 34 healthy adults used a temperature-controlled mattress cover at home for 7 nights with the feature on and 7 nights with it off.
• What the numbers showed: With it on, people rated their sleep and thermal comfort better, but measured sleep, heart rate and breathing did not change significantly.
• What this means for you: A cooling cover may make bed feel more comfortable. The authors say part of the effect may be expectation or placebo.

DOI: 10.3390/clockssleep7040055 | Clocks & Sleep

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Sleep Position and Apnea Sleep and Breathing

Vol. 8, Issue 4, pp. 193-200

Elevated Posture for the Management of Obstructive Sleep Apnea

By M. A. Skinner, R. N. Kingshott, D. R. Jones, S. D. R. Homan and D. R. Taylor

Sample: N = 14 Study Type: Randomized Crossover Trial

• What was tested: 14 adults with mild to moderate sleep apnea tried a pillow that raises the head and shoulders and a CPAP airway pressure machine, in random order.
• What the numbers showed: On the elevation pillow, breathing pauses and shallow breaths fell from an average of 27 to 21 an hour, and 4 of 14 met the success mark. On CPAP the average was 5, and 12 of 14 met it.
• What this means for you: Sleeping raised helped some people but not most, and CPAP worked far better. The study used a special pillow, not an adjustable bed base.

DOI: 10.1007/s11325-004-0193-1 | Sleep and Breathing

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Infant Sleep Safety Pediatrics

Vol. 111, Issue 5 Pt 2, pp. 1207-1214

Sleep Environment and the Risk of Sudden Infant Death Syndrome in an Urban Population: The Chicago Infant Mortality Study

By F. R. Hauck, S. M. Herman, M. Donovan, et al.

Sample: 260 cases + 260 controls Study Type: Case-Control Study

• What was tested: Researchers compared 260 infants who died of SIDS in Chicago from 1993 to 1996 with 260 matched living infants.
• What the numbers showed: A soft sleep surface was linked to about 5 times the odds of SIDS (unadjusted odds ratio 5.1, 95% CI 3.1 to 8.3), and stayed significant after adjustment.
• What this means for you: Put babies on their back on a firm, flat surface with no pillows or soft bedding, as the American Academy of Pediatrics recommends.

DOI: 10.1542/peds.111.S1.1207 | Pediatrics

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New Mattress Adjustment Health Science Reports

Vol. 7, Issue 4, Article e2046

Effectiveness of a Grid Mattress on Adults' Sleep Quality and Health: A Quasi-Experimental Intervention Study

By M. Breus, S. L. Hooper, T. Lynch, M. Barragan and H. A. Hausenblas

Sample: N = 39 Study Type: Before-and-After Study

• What was tested: 39 adults with occasional sleeplessness slept 1 week on their own mattress, then 8 weeks on a new medium-firm grid mattress, with questionnaires at weeks 1, 2, 3, 4 and 8.
• What the numbers showed: The average Pittsburgh Sleep Quality Index score (lower is better) fell from 7.49 to 5.46 after week 1 and was 4.92 at week 8.
• What this means for you: Sleep can change quickly on a new mattress. There was no control group, and the mattress maker helped fund the study. It did not study returns.

DOI: 10.1002/hsr2.2046 | Health Science Reports

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Partner Motion & Sleep Perceptual and Motor Skills

Vol. 89, Issue 1, pp. 209-217

Influence of Lateral Motion Transfer on Sleep

By J. J. Wellman, M. Bohannon and G. W. Vogel

Sample: N = 24 Study Type: Sleep Lab Study

• What was tested: 24 adults slept on one side of a king-size mattress while a 240-lb roller rocked on the other side for about 13% of sleep time. They were randomly assigned to 3 mattress designs.
• What the numbers showed: On nights the roller moved, sleepers had more light Stage 1 sleep and less deep Stage 3/4 sleep. The changes were larger on the mattresses that passed along more motion.
• What this means for you: Less motion transfer may mean deeper sleep next to a restless partner. The study does not name the mattress designs, so it does not compare pocket coils.

DOI: 10.2466/pms.1999.89.1.209 | Perceptual and Motor Skills

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Foam Durability & Firmness Applied Sciences

Vol. 14, Issue 21, Article 10016

Investigating the Impact of Long-Term Use on Mattress Firmness and Sleep Quality: Preliminary Results

By Z. Vlaović, N. Klarić and D. Domljan

Sample: 2 mattresses Study Type: Lab Wear Test

• What was tested: A machine wear test on 2 mattresses, one with a polyurethane foam core and one with a pocket spring core, using a modified EN 1957 method.
• What the numbers showed: The foam mattress lost 3.79 mm of height and its hardness settled at 8.60 N/mm. The pocket spring mattress lost 2.86 mm, and its hardness fell from 5.86 to 5.21 N/mm.
• What this means for you: Both samples kept most of their firmness in this test. With only 2 mattresses, it cannot predict how long any brand will last.

DOI: 10.3390/app142110016 | Applied Sciences

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Foam Emissions and Indoor Air Environmental Science & Technology

Vol. 53, Issue 15, pp. 9171-9180

Volatile Organic Compound Emissions from Polyurethane Mattresses under Variable Environmental Conditions

By Kira Oz, Bareket Merav, Sabach Sara and Dubowski Yael

Sample: 8 mattress types Study Type: Lab Chamber Study

• What was tested: Pieces of 8 polyurethane foam mattresses for infants, toddlers and youth were tested in air-flow chambers for 18 chemicals (VOCs), in room air and in warmer, sleep-like air.
• What the numbers showed: Emissions rose significantly in sleep-like conditions, mostly because of heat. Most estimated doses were well below risk reference levels, but a few chemicals could reach levels of concern for infants and young children.
• What this means for you: Warm foam gives off more chemicals. The study did not measure health effects or how fast emissions fade after unboxing.

DOI: 10.1021/acs.est.9b01557 | Environmental Science & Technology

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Pressure Ulcer Prevention Cochrane Database of Systematic Reviews

2021, Issue 5, CD013621

Foam Surfaces for Preventing Pressure Ulcers

By C. Shi, J. C. Dumville, N. Cullum, S. Rhodes and E. McInnes

Sample: 29 trials, 9,566 people Study Type: Cochrane Systematic Review

• What was tested: Cochrane reviewers pooled 29 randomized trials with 9,566 people, mostly older hospital patients, comparing foam beds, mattresses or overlays with other surfaces for preventing bedsores.
• What the numbers showed: Low-certainty evidence suggests foam may raise the risk of new bedsores compared with alternating pressure air surfaces (risk ratio 1.59) and reactive air surfaces (risk ratio 2.40).
• What this means for you: The type of surface matters for people at risk of bedsores. The review did not study healthy sleepers or home mattresses.

DOI: 10.1002/14651858.CD013621.pub2 | Cochrane Database of Systematic Reviews

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Infant Sleep Safety Pediatrics

Vol. 150, Issue 1, e2022057990

Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment

By R. Y. Moon, R. F. Carlin and I. Hand, for the American Academy of Pediatrics

Sample: Not a single study Study Type: Policy Statement

• What was tested: The American Academy of Pediatrics' 2022 policy statement on safe infant sleep, written by its expert task force and backed by a companion evidence report.
• What the numbers showed: About 3,500 U.S. infants die of sleep-related causes each year, and the rate has stayed about the same since 2000.
• What this means for you: Put babies to sleep on their backs on a firm, flat surface with no incline and no soft bedding, and share a room but not a bed.

DOI: 10.1542/peds.2022-057990 | Pediatrics

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Latex vs Foam Pressure Journal of Chiropractic Medicine

Vol. 16, Issue 1, pp. 1-9

Effects of Mattress Material on Body Pressure Profiles in Different Sleeping Postures

By F. Z. Low, M. C. Chua, P. Y. Lim and C. H. Yeow

Sample: N = 20 Study Type: Pressure Mapping Study

• What was tested: 20 people lay on a latex and a polyurethane foam mattress in 3 postures for 6 minutes each while a pressure mat recorded body pressure.
• What the numbers showed: Latex lowered peak pressure on the torso and buttocks and spread pressure more evenly than polyurethane foam.
• What this means for you: Latex may relieve pressure points better than basic foam. We found no published study comparing pocket springs with latex for the spine.

DOI: 10.1016/j.jcm.2016.09.002 | Journal of Chiropractic Medicine

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Sleep Position & Back Pain Applied Ergonomics

Vol. 42, Issue 1, pp. 91-97

Effect of Prescribed Sleep Surfaces on Back Pain and Sleep Quality in Patients Diagnosed with Low Back and Shoulder Pain

By B. H. Jacobson, A. Boolani, G. Dunklee, A. Shepardson and H. Acharya

Sample: N = 27 Study Type: Before-and-After Study

• What was tested: 27 adults with low back pain rated pain and sleep daily for 21 days on their own beds, then for 12 weeks on medium-firm mattresses layered for their sleep position.
• What the numbers showed: Back pain, stiffness and sleep quality improved, and back pain kept improving through weeks 8 to 12. The abstract does not give the size of the changes.
• What this means for you: Sleep position may matter when choosing a mattress. There was no control group. This replaces a federal guide that could not be found.

DOI: 10.1016/j.apergo.2010.05.004 | Applied Ergonomics

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