Comprehensive Word Lists
The individual word lists available here at OnTrack Reading are offered free for you to download and use as you please. (For your convenience, the full set can also be purchased as either a single-volume eBook or a spiral-bound book.)
How the Lists Were Created
The source of the words for the lists was The Kingfisher Illustrated Pocket Dictionary, an illustrated dictionary for children age 9 and up.The dictionary has approximately 8,500 primary entries, of which about 7,000 were used, including nearly all of the one-syllable and two-syllable words, so the lists contain most of the root words in the speaking vocabulary of a young child.
Each word was entered into a database program and broken down into its component sounds with the number of syllables also entered for each word. This resulted in a 7,000 word database that can be searched for, say, all two-syllable words containing the sound /sh/.
In addition, each sound was matched to its spelling, so not only could all two-syllable words containing the sound /sh/ be located, but so could the subset of such words where the /sh/ sound was spelled, say, "ci." This search would generate words like special and crucial, while ignoring words like ship and nation, for example.
How Comprehensive are the Lists?
If it's a reasonably common one-syllable word, it's probably in the database.
Many two syllable words, however, were left out if they were compound words. For example background, backside, backstage, and backstroke were left out, although backbone and backpack were included.
Words not likely to be used by a child were omitted, such as cockatoo, cockle, and cockerel.
Extensions were sometimes omitted, so although backward and publish were included, backwards and publisher were not. Also, root words with suffixes are usually omitted, so while love and lovely are in the database, lover, loving, loved and lovable are not.
Of the longer words, approximately one-third were omitted. For example from page 154 the words pottery, poverty, practical, precaution, precious, precipice, prejudice, premises, and premium were included, while practically, predecessor, and prehistoric were not.
The Sense in Which the Lists Are Comprehensive
If the word list claims to list one-syllable words with the sound /ow/, for example, then every one-syllable word in the 7,000 word database that contains the sound /ow/ should be on that particular list.
If the word list claims to list just words with the sound /z/ spelled se, then every word in the 7,000 word database that contains that spelling se representing the /z/ sound will appear on that list.
Are there more words with an /ow/ sound in them, or more where /z/ is spelled se? No doubt there are, but if they aren't in the database, they aren't on any of the lists.
Before you download a particular list, you might be interested in reviewing Organization of the Word Lists.