Progress in International Reading Literacy Study (pirls)

participating country. 
•
In 2011, the PIRLS and TIMSS assessment cycles came 
together, providing a unique opportunity for countries to 
collect reading, mathematics, and science achievement 
data on the same fourth grade students. 
•
Also in 2011, IEA introduced a less difficult version of 
PIRLS—called prePIRLS—as a way for countries with 
developing education systems to assess reading at the end 
of primary school and as a stepping stone to participating 
in PIRLS. 
•
In 2016, PIRLS was expanded to include two new 
assessments of reading comprehension, PIRLS Literacy 
and ePIRLS. The PIRLS Literacy assessment is 
equivalent to PIRLS in scope and reflects the same 
conception of reading as PIRLS, except it is less difficult 
overall. ePIRLS is an innovative assessment of online 
reading, designed to be responsive to the information age 
and provide important information about how well 
students are developing 21st century skills. 
Future Plans 
The next administration is scheduled for 2021. PIRLS 2021 
will be the new assessment, digitalPIRLS, which includes 
PIRLS and ePIRLS, and will be administered in a complete 
computer-based delivery system. 
5. DATA QUALITY AND 
COMPARABILITY 
Comparisons made
in
PIRLS (e.g. education
systems’
averages compared to the U. S. average) are tested for 
differences using statistical significance, which requires the 
estimation of standard errors. However, the estimation of 
correct standard errors is complicated by the complex 
sample and assessment designs of PIRLS: both the sample 
design and assessment design generate error variance and 
mandate a set of statistically complex procedures. For 
PIRLS, estimates produced using the data are subject to two 
types of error—nonsampling and sampling error. 
Nonsampling error can be due to errors made in collecting 
and processing data. Sampling error can occur because the 
data were collected from a sample rather than a complete 
census of the population.