Table 4 Education-related inequalities in maternal healthcare utilization among women aged 15–49 years in Nigeria: 2003–2018

1998

0.508(0.298 to 0.717)

0.493(0.290 to 0.697)

0.674(0.561 to 0.786)

0.586(0.488 to 0.684)

0.542(0.418 to 0.665)

0.261(0.202 to 0.320)

1999

0.413(0.264 to 0.563)

0.412(0.263 to 0.562)

0.617(0.526 to 0.708)

0.497(0.424 to 0.570)

0.579(0.496 to 0.662)

0.493(0.423 to 0.564)

2000

0.578(0.492 to 0.664)

0.578(0.492 to 0.664)

0.663(0.590 to 0.736)

0.607(0.540 to 0.674)

0.646(0.569 to 0.723)

0.609(0.536 to 0.681)

2001

0.561(0.496 to 0.626)

0.561(0.496 to 0.626)

0.631(0.539 to 0.723)

0.571(0.488 to 0.654)

0.631(0.531 to 0.731)

0.581(0.489 to 0.673)

2002

0.529(0.469 to 0.589)

0.528(0.468 to 0.587)

0.617(0.545 to 0.688)

0.547(0.483 to 0.610)

0.600(0.532 to 0.667)

0.550(0.488 to 0.611)

2003

0.525(0.386 to 0.664)

0.469(0.345 to 0.593)

0.653(0.602 to 0.703)

0.644(0.595 to 0.694)

0.512(0.445 to 0.579)

0.202(0.176 to 0.229)

2004

0.565(0.501 to 0.629)

0.556(0.493 to 0.618)

0.660(0.624 to 0.695)

0.598(0.566 to 0.630)

0.669(0.635 to 0.703)

0.619(0.587 to 0.650)

2005

0.595(0.550 to 0.639)

0.594(0.550 to 0.638)

0.681(0.648 to 0.714)

0.606(0.577 to 0.636)

0.683(0.651 to 0.715)

0.632(0.602 to 0.662)

2006

0.577(0.543 to 0.612)

0.576(0.542 to 0.610)

0.660(0.624 to 0.696)

0.594(0.562 to 0.626)

0.664(0.630 to 0.698)

0.621(0.589 to 0.653)

2007

0.578(0.543 to 0.613

0.578(0.543 to 0.612)

0.671(0.636 to 0.707)

0.600(0.568 to 0.631)

0.666(0.633 to 0.699)

0.622(0.591 to 0.653)

2008

0.619(0.542 to 0.695)

0.607(0.532 to 0.682)

0.636(0.598 to 0.675)

0.603(0.567 to 0.640)

0.566(0.521 to 0.611)

0.400(0.368 to 0.432)

2009

0.650(0.599 to 0.701)

0.643(0.593 to 0.694)

0.676(0.641 to 0.711)

0.598(0.567 to 0.629)

0.694(0.659 to 0.729)

0.636(0.604 to 0.668)

2010

0.534(0.491 to 0.578)

0.534(0.491 to 0.578)

0.625(0.588 to 0.661)

0.566(0.533 to 0.598)

0.655(0.620 to 0.690)

0.608(0.576 to 0.641)

2011

0.555(0.517 to 0.592)

0.549(0.512 to 0.586)

0.626(0.591 to 0.660)

0.588(0.556 to 0.620)

0.657(0.623 to 0.691)

0.631(0.599 to 0.664)

2012

0.525(0.487 to 0.562)

0.524(0.486 to 0.561)

0.640(0.607 to 0.673)

0.595(0.565 to 0.626)

0.662(0.630 to 0.695)

0.630(0.599 to 0.661)

2013

0.542(0.360 to 0.724)

0.446(0.296 to 0.595)

0.614(0.549 to 0.678)

0.613(0.549 to 0.678)

0.487(0.418 to 0.555)

0.130(0.112 to 0.149)

2014

0.573(0.520 to 0.626)

0.521(0.472 to 0.569)

0.635(0.604 to 0.665)

0.598(0.569 to 0.627)

0.672(0.644 to 0.700)

0.650(0.623 to 0.676)

2015

0.525(0.482 to 0.568)

0.502(0.460 to 0.543)

0.650(0.621 to 0.680)

0.613(0.585 to 0.641)

0.681(0.653 to 0.709)

0.658(0.630 to 0.685)

2016

0.488(0.452 to 0.525)

0.481(0.445 to 0.517)

0.633(0.605 to 0.662)

0.610(0.583 to 0.637)

0.675(0.649 to 0.701)

0.665(0.639 to 0.691)

2017

0.496(0.464 to 0.527)

0.483(0.452 to 0.513)

0.608(0.576 to 0.640)

0.592(0.561 to 0.624)

0.658(0.629 to 0.687)

0.650(0.622 to 0.679)

Time trend coefficient (P-value)

0.0003(−0.004 to 0.005) (0.874)

−0.001(−0.006 to 0.004) (0.697)

−0.001(−0.003 to 0.0004) (0.132)

0.002(−0.0004 to 0.004) (0.104)

0.004(− 0.001 to 0.008) (0.132)

0.008(− 0.005 to 0.021) (0.198)