Table 1.
Characteristics of included studies
| Characteristic | N (%) |
|---|---|
| Study related | |
| Year of publication | |
| 2010 to present | 14 (41) |
| 2000–2009 | 10 (29) |
| Pre-2000 | 10 (29) |
| Country of publication | |
| United States | 20 (59) |
| The Netherlands | 3 (9) |
| Canada | 2 (6) |
| Egypt | 2 (6) |
| Finland | 2 (6) |
| Other | 5 (15) |
| No. of patients per study (n) | |
| 0–99 | 27 (79) |
| 100–199 | 5 (15) |
| 200+ | 2 (6) |
| Study design | |
| Cross-sectional | 25 (74) |
| Cohort | 9 (26) |
| Patient related | |
| Mean age, yra | |
| 0–6 | 3 (9) |
| 7–12 | 16 (47) |
| 13+ | 13 (38) |
| Stages of CKDb | |
| Mild to moderate stage CKD | 25 (74) |
| Dialysis | 6 (18) |
| Transplant | 15 (44) |
| Use of controlsb | |
| Direct non-CKD controls | 19 (56) |
| Normative population data | 28 (82) |
| Test related | |
| Outcome domains | |
| Intelligence | 25 (74) |
| Academic achievement | 10 (29) |
| Attention | 11 (32) |
| Executive function | 9 (26) |
| Memory | 12 (35) |
| Intelligence | |
| Wechsler scales (IQ) | 22 (65) |
| Stanford Binet Intelligence Test | 2 (6) |
| Test of nonverbal intelligence | 1 (3) |
| Other | 9 (26) |
| Attention | |
| Conners Continuous Performance Task | 5 (15) |
| Continuous performance taskc | 3 (9) |
| Gordon Diagnostic System | 2 (6) |
| Other | 8 (24) |
| Executive function | |
| Behavior Rating Inventory of Executive Function | 5 (15) |
| Delis–Kaplan Executive Function System | 2 (6) |
| Halstead–Reitan Category Test | 2 (6) |
| Other | 8 (24) |
| Memory | |
| Wide range assessment of memory and learning | 5 (15) |
| Nonverbal selective reminding test | 2 (6) |
| Other | 9 (26) |
| Academic achievement | |
| Wechsler Individual Achievement Test | 6 (18) |
| Wide Range Achievement Test | 3 (9) |
| Peabody Individual Achievement Test | 2 (6) |
| Other | 2 (6) |
| Subtestsc | |
| Full-scale IQ | 21 (62) |
| Verbal IQ | 18 (53) |
| Performance IQ | 16 (47) |
| Reading | 8 (24) |
| Arithmetic | 8 (24) |
| Spelling | 4 (12) |
IQ, intelligence quotient.
a
Two studies did not specify.
b
There is overlap in the number of studies.
c
Not all studies reporting outcomes contained data suitable for meta-analysis.