Introduction to the Diagnostic Decision-Making Model

The website presents and briefly describes the diagnostic decision-making model presented in
Practical Steps for Informing Literacy Instruction: A Diagnostic Decision-Making Model
(Michael W. Kibby, 1995, International Reading Association).

(See also the accompanying information on PREPARING TO WRITE INSTRUCTIONAL RECOMMENDATIONS)

Some Presumptions of the Model of the Diagnostic Decision-Making Process
It is assumed that diagnostic assessment is a process, not a product. To be sure, diagnostic
processes often do end in a “report” that is the basis of future reading instruction, but the report
is not the diagnosis, it is the result of the diagnostic process. The presumption of this diagnostic
decision-making model is that diagnostic assessment of reading difficulties is a problem-solving
process. This problem-solving process has four steps.

1.
2.
3.
4.

Identifying needed information.
Obtaining that information.
Interpreting and evaluating information.
Determining further information needed (if any).

This decision-making model is not a guide to finding causes of reading problems—seeking the
cause of a child’s reading difficulty is futile. The goal of the diagnostic process is to ascertain
instructional goals, techniques, and materials that will speed up the child’s progression in
reading—not trying to figure out the cause of the reading difficulty. This decision-making model
is child-centered, and reflects an interactive view of reading. If every child learned to read by
learning the same skills taught in a standard manner, there would be no need for diagnostic
assessment. Diagnosis is also conceived here as interpretive in nature.

General Orientation to the Model

Overview of the Model
The model is discussed in two parts. Discussed first is the central strand or core which
demonstrates the start of the diagnostic process, various major stages in the process, and the
expected results from the diagnostic process. The total model will then be discussed. The model
(which emanates above and below the central strand) is hierarchically ordered. Five questions
guide the diagnostic decision-making process, each of which is reflected in the model.
1.What is the child’s current reading ability and is it satisfactory?
2.Which reading strategies/skills are strengths and limitations for the child?
3.What factors might be associated with reading ability?
4.What are the most favorable instructional conditions for the child?
5.What are the recommendations for the child (reading and other)?

Brief Introduction to the Central Strand of the Model
The core of the diagnostic decision-making model—the central strand—moves left to right
starting with the “Child . . . Child’s Educational, Psycho-Social and Developmental History”
(first box on the left) and ending at “Instructional Modifications / Continued Evaluation” (the last
circle on the right). This left-to-right progression of the model parallels the sequence of
assessment.

The center strand of the model - click on the figure for an enlarged view

The second box on the central strand (“Reading Ability: Achievement/School Performance . . .
Expected Level of Performance”) represents the process of (a) assessing the child’s current
reading status or performance and (b) determining if that reading ability is satisfactory given the
child’s expected level of ability. The next stage of the process is “Analysis of Oral Reading
Performance.” Oral reading analysis is followed by an evaluation or decision—represented by
the little black spot; that decision is, does the child have a reading problem? If the answer is yes,
we move to “Word Recognition / Reading Comprehension.” It is here that the first upward and
downward emanations from the central strand occur. Every diagnostic assessment includes
measurements, assessments and evaluations of both word recognition and reading
comprehension, but the role of this box in the model is to economize time and effort by utilizing
previous reading information (i.e., reading ability and oral reading) to determine where attention
should be focused primarily, or at least first: on reading comprehension and all its strands and
components or on word recognition and all its strands and components.

It must be made clear that this “Word Recognition / Reading Comprehension” box does not
imply that all of a child’s reading problems or instructional needs are either strictly word
recognition or strictly reading comprehension, nor does it imply that word recognition and
reading comprehension are unrelated, and it does not even imply that word recognition and
reading comprehension are the only two important skills or strategies in reading. It is recognized
that comprehension aids word recognition, and that there is no or reduced comprehension when
word recognition is absent or extremely difficult. All diagnoses evaluate some components of
word recognition and some components of reading comprehension.

The first of three circles is next on the central strand, “Summative Evaluation of Reading
Abilities.” Circles indicate a point of reflection in which one or more of the five questions
guiding the diagnostic process is answered: the first two questions being answered in the first
circle (What is the child’s current level of reading ability and is it satisfactory? and Which
reading strategies/skills are strengths and limitations for the child?). This circle is followed by
the “Associated Factors” box, which indicates the process ascertaining if any environmental,
physical, language, psychological or other factors might be associated with the child’s reading.

The next step, indicated by the “Diagnostic Teaching” box, is to evaluate the student’s learning
in a variety of instructional conditions—this is the most important step in diagnosing—if not the
heart of the model. A fundamental rationale of this diagnostic decision-making model is that one
cannot recommend appropriate goals, objectives, teaching methods, or instructional materials for
a given child without having taught that child real and meaningful content that he or she needs to

learn using teaching methods that can be used by others and instructional materials that are
available.

Utilizing all the information collected and summative evaluations made, the content and nature
of the necessary reading instruction are formulated, the “Formative Evaluation of all Factors”
circle; this also answers the third and fourth questions guiding the diagnosis (What factors might
be associated with reading ability? and What are the most favorable instructional conditions for
the child?) After taking into account “Present and Available Instructional Situations” and
adjusting these formative evaluations if necessary, the recommended instructional modifications
are stated and implemented (the last circle), which also answers the last of the five questions
(What are the recommendations for the child (reading and other)?).

The Full Model and an Overview of Its Upward and Downward Emanations
There are three sets of emanations outward from the center strand (above and below): first, from
the “Word Recognition / Reading Comprehension” box are the specific word recognition and
reading comprehension components that must be taken into account; second, from the
“Associated Factors” box are the language, physical and affective factors that may or must be
taken into account; and third, from the “Diagnostic Teaching” box are the aspects of readers and
texts that must be taken into account in selecting appropriate materials for instruction.

The complete model - click on the figure for an enlarged view

Some components above and below the center strand are encased in solid-lined boxes, others in
broken-line boxes, and some are underscored. As indicated in the key, solid-line boxes and
circles designate an essential component in the diagnostic process; that is, no diagnosis can be

complete without an evaluative decision on each of these components. Solid lines are also used
to encase the components “Sight Vocabulary,” “Context Strategies for Word Recognition,”
“Word Analysis Skills . . . ,” and “Non-Directed Reading of Narratives and Expositions.” This
means that the diagnostic process must result in evaluative statements about each of these
components—however, evaluation does not necessarily mean specifically assessed or tested.
Two examples follow.

•

If it is observed during oral reading (the third box on the center strand) that a third-grade girl
has minimal difficulty identifying words as sight vocabulary on third- and fourth-grade text
and that she efficiently applies word analysis strategies on those few words not recognized
automatically, then it is possible to formulate evaluative statements about “Sight Vocabulary”
and “Word Analysis Strategies: Synthesizing/Segmenting of Written Words” without
administering specific tests of those abilities or strategies.
Similarly, if a child comprehends a passage when given no instructional assistance,
“Nondirected Reading of Narratives and Expositions,” then it is not necessary to determine if
the child knows the sense or meaning of specific words in that passage(s).

•

Many—indeed, most—of these variables above and below the central strand are enclosed in
broken lines, indicating that they are subordinate components—meaning that they are
specifically assessed and evaluated only when the child has not succeeded on tasks higher in the
hierarchy. Two examples follow.

•

If a child reading fairly easy texts did not apply word recognition strategies to identify those
few words not instantly recognized, then the “Word Analysis Strategies: Synthesizing / . . .”
component must be specifically assessed to evaluate the child’s knowledge of phonics.
In the case of a child with extremely limited word recognition abilities during oral
reading—difficulty reading a pre-primer text—it might be necessary to test the child’s ability
to read words at the pre-primer, primer, or first grade levels. If the child has a minimal sight
vocabulary, say 10 or 15 words, one would move further up (in terms of the model, but down
in terms of reading ability) to “Ability to Learn Sight Vocabulary.” Here the child would be
taught specific words to determine if he or she is able to recall them.

•

The black spots indicate stop-decision points, at which one must make an evaluation and decide
if these subordinate-level reading abilities or associated factors must be specifically assessed in
order to be evaluated. An evaluation of a child’s reading must account for every variable or
component (indicated by a box, broken-line box, circle, or underline); however, “accounted for”
is not to be interpreted to mean specifically assessing or testing. Because of the hierarchical
ordering of the model, information used to “account for” a variable may be gleaned from more
general measures or presumed on the basis of ability to perform higher order skills or strategies;
though sometimes it must be obtained by individually assessing the specific variable.

Underlined components deserve special mention. Like broken-line boxed components, they are
considered only after a child has demonstrated limitations in higher order components. The
underlined components, however, are all tangential to reading and do not come into play until it
has been found that the child is unable to learn any reading skills—which means that these
tangential skills are never assessed! In all my years of diagnosing and teaching school-aged
children, I have never found it necessary to assess a specific child’s visual discrimination of
forms or auditory memory of numerals or isolated words. One might ask then, why keep these

“tangential components” in the model. They serve a useful purpose, indeed, they are the genesis
of the model itself. Over the years, I have seen innumerable reports of diagnoses done by some
reading teachers and many other professionals in a variety of educational or psychological
clinics; hundreds of these reports have included the testing of “perceptual skills,” even if the
child being tested had already learned to read (albeit, not well), already possessed a substantial
(though not sufficient) sight vocabulary, and was able to deploy some (but not enough)
graphophonic strategies. There is no need to determine a child’s status on perceptual skills when
the child has already learned even a few of the reading strategies or skills that these perceptual
skills are thought to precede. It was once theorized that the dominant perceptual modality of a
child’s reading instruction should match his or her modality preference or strength as determined
by tests of auditory and visual discrimination and memory (e.g., this theory stipulated that a child
with a stronger visual modality than auditory should be taught by visual or sight-word
instruction). In spite of the fact that literally dozens of research studies since the mid-1950s (e.g.,
Robinson, 1972) have provided data that undermine the validity of this theory, I still see report
after report in which WISC-R or WISC-III subtest patterns and the results of various perceptual
tests are analyzed and used as the basis for recommending that a child receive a visual-based or
auditory-based instructional program. These perceptual skills are left in the model as a reminder
that they are to be assessed only when a child has absolutely no reading or literacy strategies at
all and is unable to learn any single reading strategy with direct instruction—which of course
never happens—thus these perceptual skills should never be directly assessed in any reading
diagnosis.