Each child car seat was thoroughly tested over a period of five months through a range of 'real world’ and standardised testing.
To do this we commissioned Alison Williams, a mum of two, to research the best high back booster seats around. Alison has written articles on a wide range of parenting topics and has previously written reviews on the best baby car seats and the best toddler car seats for Mumsnet.
Who tested the car seats?
Alison partnered with parent tester, Jemma, whose five-year-old daughter used the car seats in the family’s Citroën Grand C4 Picasso. The seats were also occasionally used by other children.
Jemma used the car seats as part of day-to-day life and tested each seat for at least a week on both shorter and longer journeys, including the school run.
We think it's really important to work with a single tester to ensure consistency in results – results that are also based on like-for-like comparison. Each car seat was then scored on six key criteria: safety and stability, assembly, day-to-day use, aesthetics, cleanliness and value for money.
Which high back booster seats did we test?
Alison spent 30 hours researching the current car seat market and crash test ratings from the likes of ADAC and Which?, and also spoke to car seat safety experts from Good Egg Car Safety and Rear-Facing Toddlers before settling on a final shortlist.
- Maxi-Cosi Kore i-Size (£169.99 on Amazon)
- BeSafe iZi Flex Fix i-Size (£249 from John Lewis & Partners)
- Britax Römer Kidfix III M (£170 from Uber Kids)
- Cozy N Safe Augusta EZFix (£90 from Uber Kids)
- Apramo Ostara Fix (£94.99 from Uber Kids)
- Maxi-Cosi Kore Pro i-Size (£219 from John Lewis & Partners)
- Cybex Solution S-Fix (£115 from Uber Kids)
- Diono Everett NXT (£99.95 from Amazon)
- Diono Monterey XT (£96.29 from Amazon)
- Recaro Monza Novo Evo Seatfix (£109 from Uber Kids)
- MyChild Expanda (£69.99 from Amazon)
Five car seats were then awarded coveted Mumsnet Best awards: the Maxi-Cosi Kore i-Size (Best Child Car Seat 2020), the BeSafe iZi Flex Fix i-Size (Best Versatile Child Car Seat 2020), the Britax Römer Kidfix III M (Best Child Car Seat for Ease of Use 2020), the Cozy N Safe Augusta EZFix (Best Value Child Car Seat 2020) and the Apramo Ostara Fix (Best Lightweight Child Car Seat 2020).
How did we test for safety and stability?
As well as analysing crash test results and general safety, we looked at additional safety features and how easy the car seat was to install – was there any room for error, did the seat feel stable when installed, where could the seat be installed in the car and was it distracting to the driver, especially if positioned in the middle?
We also made note of the materials used to check for both durability and irritability, studying everything from the fabric to the padding, and also reported on how comfortable the child was in the seat overall.
How did you test for assembly?
We made sure to time assembly and measure the general intuitiveness of the process.
Were clear instructions provided? Was the seat simple to install? Did it require more than one person to do it and were any details available online if you got stuck?
How did you test for day-to-day use?
We put each seat through its paces for ease of getting a child in and out of the car, adjusting straps, padding and headrest height, and allowing children to buckle themselves in.
We also considered how the car seat would work with multiple children – whether you could fit two or three car seats next to each other, and how easy it was to switch between vehicles.
Longevity is also a key factor so we noted whether the seat could 'grow' with your child and if it would be suitable for children of varying ages.
Lastly, we carried out a ‘comfort and joy’ test. In essence, this was asking whether our mini tester was comfortable in the seat and whether the car seat could make parents’ lives easier.
How did you test for aesthetics and cleanliness?
When it came to aesthetics, there were predominately three main questions: how did the seat look? Was the fabric good quality and would the seat appeal to both a six-year-old and a child at the top end of the car seat's age range (age 12)?
How easy the seat was to clean was also a major consideration. We spilled both milk and juice on each seat to see how it fared after cleaning and looked at whether covers could be removed for machine washing – and, crucially, put back on without hassle.
How did you test for value for money?
Having scored each car seat on the above criteria, we then added into the equation price and how long it would last (the maximum age or weight) to work out which model was the best of the best and which others deserved honourable mentions.
Why you should trust us
Mumsnet has been making parents’ lives easier since 2000 and, in those years, we’ve seen, tried and reviewed countless products. We’ve watched trends come and go and safety features become more and more slick. Our testing is best in class – we rigorously test each product with real children in real-life situations as well as standardised lab-style testing and we're confident that our testing leaves no stone unturned. This means that parents don’t need to compare reviews or hunt around for other opinions. They know Mumsnet has it covered.
About Mumsnet Reviews
All Mumsnet product reviews are written by real parents after weeks of research and testing. We work hard to provide honest and independent advice you can trust – brands can’t pay to win a Mumsnet Best award.
The aim of Mumsnet Reviews is to produce the best product reviews on the market for parent and baby products. We do sometimes earn revenue through affiliate (click-to-buy) links in our articles. However, we never allow this to influence our coverage.
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