Key questions for parents choosing childcare published
A new checklist for parents trying to decide which nursery or childminder to use will be published on Tuesday.
The Daycare Trust's guide says parents in England should not rely on Ofsted reports alone when choosing between childcare providers.
A spokeswoman for Ofsted said parents should look at a range of information, including inspection reports.
The checklist includes first impressions, costs, staff ratios and what happens in an emergency.
The guide, How to Find High Quality Childcare, says parents should always visit different nurseries or childminders before making a decision.
"Recommendations from other parents can be helpful, but it is important to remember that everyone is different and what suits their child will not necessarily suit yours," it advises.
The guide also says that by choosing childcare which is registered with Ofsted, parents know that the childcare provider has been approved to care for children.
Ofsted 'too broad'
But research published by Daycare Trust alongside the checklist suggests that Ofsted's grading system is too broad to provide parents with a detailed measure of the quality of childcare providers.
Ofsted uses the same basic grading system for childcare as it does for schools.
So nurseries and childminders are divided into four grades: outstanding, good, satisfactory and poor.
The research, carried out by researchers from Oxford University, concluded that these grades lack detail, particularly when applied to care for children under two-and-a-half years old.
"Ofsted grades cannot necessarily be relied upon as a complete measure of quality, and may need to be completed by other measures," said Sandra Mathers, lead researcher from Oxford's Department of Education.
Daycare Trust suggests that the inspections carried out by local authorities often use international grading systems which are more precise and stringent than Ofsted's.
In a statement Ofsted said: "We agree with the report that a full picture of quality comes from consideration of a range of measures, including Ofsted inspections.
"This report is timely as it comes during our consultation on proposals for changes to inspection from September 2012.
"Those proposals already cover a number of issues raised in this report particularly about making reports easier to understand and more accessible to parents."