Design Factors for Evaluating Child Resistant Packaging
Condition: Unintentional Injury
MeSH terms: Accidental Injuries
Study type: Observational

Summary: 
      Each year over 59,000 children under the age of 5 are taken to emergency rooms (equivalent to
      4 busloads of children arriving every day to the ER) because they were able to get into
      medication containers unsupervised. 95 percent of these ER visits occurred due to the child
      getting into medicine when an adult was not looking.

      Child resistant containers (CRC) are intended to restrict entry by imposing a cognitive
      barrier (the child must understand how to operate the CRC mechanism in order to open it) and
      a physical barrier (the child must posses the motor skills necessary to operate the CRC).

      We are testing a design which changes the physical area available for grip utilizing
      anthropometric data that, in theory, would exclude children and enable adults.

      We will evaluate the proposed design's effectiveness in two ways (1: cognitive barrier) will
      the child understand where they need to specifically grip the cap with their fingers and (2:
      physical barrier) will the child be able to use an appropriate gripping strategy to apply
      enough torque to rotate the cap and open it.
    

Detailed description: 
      In order to evaluate the effectiveness of cognitive and physical barriers as child resistant
      design features, we are testing designs which change the physical area available for grip
      utilizing anthropometric data that, in theory, would exclude children and enable adults.
      Testing will be conducted with children aged between 42-54 months of age. Our testing is
      adapted from testing dictated by 16 CFR 1700; this testing is mandated by the Poison
      Prevention Packaging Act of 1970 and is used throughout the United States (and, in fact,
      adapted by much of the world) to verify the performance of child resistant packaging. The
      maximum age limit specified by 16 CFR 1700 is 51 months so the child testing for this study
      represents a more severe test of the closure.

      One type of package is being tested: a 38mm diameter neck 400 thread finish (38/400) bottle
      that is typical of what is used to hold over-the-counter (OTC) medications. The bottle is
      outfitted with a two-piece continuous thread screw cap closure. Three treatments of the screw
      cap are being evaluated. One treatment attempts to restrict children from accessing the
      package using a cognitive paradigm (design intuitiveness for opening) the second treatment
      leverages a physical paradigm (anthropometric characteristics of the hand to keep them out)
      and the third treatment, the control, is a standard OTC push-down and turn child resistant
      screw cap.

      Summary

      Children will be recruited with the help of the Michigan State University Child Development
      Labs (MSU CDL) and testing will take place in a designated room within the Wilkshire Early
      Childhood Center in Haslett, Michigan and/or Early Learning Institute (ELI) preschool in East
      Lansing, MI. Approximately 120 children will test a single treatment of the three (N=40 per
      treatment); attempts will be made to counterbalance age and sex by treatment . The width of
      each child's thumbs will be measured by taking a digital photographic with their hand place
      on a grid of known dimensions. Testing will then occur in two 5 minute segments for each
      treatment (as with the regulated protocol overseen by CPSC).
    

Intervention name(s): Novel approaches for the design of child resistant closures
Intervention type(s): Other
Intervention description(s): Two novel designs for child resistant closures are tested.
One is sized based on the anthropometric properties of adults and children's hands such that it should disallow children from engaging the system and enable adults (the physically based design strategy). The other replicates the first design, but is sized such that either of the two populations should be able to engage the closure.
In testing this way, we begin to differentiate the paradigm that holds the children out (the cognitively based design strategy-- they do not understand and/or a physical one- they are unable to use the closure).
Results (proportion of children opening within the first or second five minute periods of test and time to opening during the same) from each of these, will be compared to results from the third treatment, a standard, commercially available push and turn system.
Observational model: Other
Time perspective: Other
Sampling method: Non-Probability Sample
Study population: 
        42-54 months of age Recruited from preschools throughout mid Michigan