Table 2 The core phenotyping and primary aims of CKD observational cohort studies

CRIB [30, 38]

To explore the relationship between CKD and CVD in individuals not receiving dialysis

12 lead ECG for assessment of LVH

Medical history; height, weight and blood pressure; urine and non-fasted blood, creatinine and eGFR (MDRD)

MMKD [31]

To explore the natural history of mild to moderate CKD and identify possible biomakers of progression

Medical history, clinical examination and blood and urine collection for biomarker analysis

LCKD [32]

To describe the course of the disease and the determinants of patient outcomes

In phase II patients from the initial phase invited to undergo echocardiography, flow mediated vasodilation, pulse wave velocity, 24 hr heart rate monitoring and spiral CT. All these investigations are done on two occasions one year apart

Health related QoL (SF36); co-morbidites and medications; blood ans urine samples for biomarker analysis

CRISIS [33]

To describe the risk factors associated with renal progression

Augmentation index and carotid-radial pulse wave velocity (SphygmoCor system); two blood pressure readings

Medical History; medication history; Blood and urine for biomarker analysis

CRIC [35, 39, 40]

To examine the risk factors for both the progression of CKD and the development of CVD

12 lead ECG and echocardiography at years 1 and 4 of follow up, sprial CT in a third of participants, pulse wave velocity (PWV) measured in 2564 participants

eGFR (MDRD in all, iothalamate in a sub-group), annual blood and urine sampling for biomarker analysis

SEEK [36]

To examine the prevalence of abnormalities in PTH, vitamin D, phosphate and calcium in patients with CKD

None

Medical history; medication history; blood and urine samples

R²ID [37]

To assess the need for specialist referral in a primary care CKD population and measure rate of change of kidney function

Pulse wave velocity and augmentation index (Vicorder system), advanced glycation end products (AGE reader system)

Socio-economic measures (IMD score); medical and medication history; anthropomorphic measures; blood and urine sampling;