DIBELS Nonsense Word Fluency
Description of the NWF Measure
The DIBELS Nonsense Word Fluency (NWF) measure is a standardized, individually administered test of the alphabetic principle including letter-sound correspondence in which letters represent their most common sounds and of the ability to blend letters into words in which letters represent their most common sounds (Kaminski & Good, 1996). The student is presented an 8.5" x 11" sheet of paper with randomly ordered VC and CVC nonsense words (e.g., sig, rav, ov) and asked to verbally produce the individual letter sounds in each word, or read the whole word. For example, if the stimulus word is "pov" the student could say /p/ /o/ /v/ or say the word /pov/ to obtain a total of three letter-sounds correct. The student is allowed 1 minute to produce as many letter-sounds as he/she can, and the final score is the number of letter-sounds produced correctly in one minute. Because the measure is fluency based, students should receive a higher score if they are phonologically recoding the word, as they will be more efficiently producing the letter sounds, and receive a lower score if they are providing letter sounds in isolation. The intent of this measure is that students are able to read unfamiliar words as whole words, not just name letter sounds as fast as they can.
The NWF measure takes about 2 minutes to administer and has over 20 alternate forms for monitoring progress.
DIBELS 6th Edition Technical Adequacy of the NWF Measure
The one-month, alternate-form reliability for NWF in January of first grade is .83 (Good, Kaminski, Shinn, Bratten, Shinn, Laimon, Smith, & Flindt, 2004). The concurrent criterion-validity of DIBELS NWF with the Woodcock-Johnson Psycho-Educational Battery-Revised Readiness Cluster score is .36 in January and .59 in February of first grade (Good et al., 2004). The predictive validity of DIBELS NWF in January of first grade with (a) CBM ORF in May of first grade is .82, (b) CBM ORF in May of second grade is .60, (c) Woodcock-Johnson Psycho-Educational Battery Total Reading Cluster score is .66 (Good et al., 2004).
How does NWF link to the Big Ideas in Beginning Reading?
NWF is a measure that assesses alphabetic principle skills. Alphabetic Principle (AP) is:
- the ability to associate sounds with letters and use these sounds to form words. It is composed of two parts:
- Alphabetic Understanding: Letters represent sounds in words.
- Phonological Recoding (blending): Letter sounds can be blended together and knowledge of the systematic relationships between letters and phonemes (letter-sound correspondence) can be used to read/decode words.
- a prerequisite to word identification.
To learn more about the Alphabetic Principle, visit the Big Ideas in Beginning Reading website.